P0700 and P0740 trouble codes on 1998 Jeep Cherokee

[Mudderoy]

A couple of days ago the check engine light came on. I didn't notice anything not performing as it always does.

I was a little concerned that the CPS was acting up, even though all seemed fine. I expected the check engine to stay off after the next off/start cycle.

It stays.

I checked it today and received the P0700 and P0740 codes.

I have researched the codes and it appears to be a transmission related issue.

I have noticed a fair amount of vibration when backing out of the driveway. I thought that perhaps the exhaust system was bounding off the cross member again because when I put it in drive the vibration goes away.

I have checked the fluid levels several times since I installed the transmission temp gauge. It just dawned on me I didn't check the level after the new radiator install. So I just checked it. It wasn't to the add, but I put about 3/4 of a quart in anyway. It's full.

I read it could be the TPS, but that's like the 2nd one I have on there.

I cleared the codes, and just now I ran the engine while checking the transmission fluid level and no check engine light.

I cycled through the gear and backed it up and went forward again. Nothing, seems fine.

Maybe I have a solenoid that is having problems talking to the computer, dunno. I'll run it and see if the check engine light comes back

If anyone has any experience with P0740 please chime in.

[xj4life2]

Here's a start for ya , it aint pretty but here ya go

http://i837.photobucket.com/albums/zz298/payless4x/po740.gif

Let me know if ya need more

[Mudderoy]

Thanks!

Well I drove it in today and no new check engine light. I'll keep monitoring it and let you know.

[Mudderoy]

Check Engine light went off yesterday. After about an hour it came back on. I suspect the torque converter solenoid.

There is a simple test to see if it has a problem, but now I am wondering if it will show up a problem in the test if the problem is coming and going away.

[Mudderoy]

I'll be really surprised it this is the solution but it's the only thing I've changed recently...

The check engine light is out and has been out yesterday and today.

I found that my cross member wasn't connected to the uni-body on the driver's side the other day when I got under the Jeep in the work parking lot to swap out the starter.

I have a factory transfer case skid that was helping to support that side of the cross member. The next morning I moved one of the 1" spacers from the passenger's side to the driver's side so that both sides of the cross member would be connected on both sides.

Sunday I installed 2 more spacers and bolts.

If the transmission was at an angle it wouldn't have been by much. The fluid level is correct, so I wouldn't think that with a full transmission and a slight tilt would cause this code to come up. Perhaps the torque converter lock/unlock solenoid needs to be replaced and it is being sensitive.

I don't know maybe the problem is still there and it will come back when the ECM sees the problem 3 times again.

[Mudderoy]

So the check engine light went off by itself, and has been off for several days now. :rolleye0012:

[xj4life2]

You had a computer Fart !!! it happens from time to time

[Mudderoy]

Well the Check Engine light has been coming on and off for a few months now. I went ahead and purchased a set of solenoids for a A340 Toyota transmission.

Well yesterday coming home the transmission wouldn't shift into 3rd gear until I hit 4,000 rpm, which basically meant it wasn't shifting via the PCM it was hitting the fail safe.

I checked the codes when I got home, P0753
Shift Solenoid ”A” Electrical

So anyway I know it could be things other than the solenoids but what the hell.

I changed them tonight. I was surprised that the replacement solenoids were so much bigger than the OEM.

https://lh6.googleusercontent.com/-066DjymFdWI/TqeTLKgSpHI/AAAAAAAABcw/cwm7WuLUi3o/s800/2011-10-25%25252019.53.41.jpg

https://lh5.googleusercontent.com/-dmsZXmScVdI/TqeRzB8BmjI/AAAAAAAABcY/wgsZqIVTnw0/s800/2011-10-25%25252020.37.20.jpg

https://lh4.googleusercontent.com/-wXahg59k7OU/TqeRI6G9TZI/AAAAAAAABcQ/rkrJ_C_Z7kw/s800/2011-10-25%25252021.28.42.jpg

[4.3LXJ]

Cool, got it running yet?

[Mudderoy]

Cool, got it running yet?

Yeah I was done with it last night at the time I posted. I got a P0740 this morning but now I'm thinking I have a faulty brake light switch.

[Mudderoy]

BTW, I ordered the solenoid set from http://www.bulkpart.com/

Code Name Quantity Price/Ea. Total
-------------------------------------------------------------------------------------------
97420K Solenoid kit, A340, 2 Shift solenoids & 1 Lock-up 1 $191.27 $191.27
Shipping: Basic UPS Ground Continental U.S.A. Only (excludes Canada HI & AK): $15.25
Sales Tax: $0.00
-------------------------------------------------------------------------------------------
Total: $206.52

[jeepxj95]

??? tony did u get those under the jeep swction or the toyota/valvo section???...... nevermind i think i found it

[Mudderoy]

??? tony did u get those under the jeep swction or the toyota/valvo section???...... nevermind i think i found it

It's been awhile but I believe they both take you to the same place. They are Toyota A340 solenoids

[jeepxj95]

i also seen that they have trans go shift kits and reprogramers they call it to take care or some of the issues. hmm only if mine died.

[Carves]

Hows those new solenoids working out mudderoy ???

Any harshness between gear changes or anything ??

Theres stories that A340 parts are different ... but I suspect the components are just more HD compared to what chrysler provided in the AW4 ??

Some of the ricer websites have mods for solenoid spacers and what not in Toyota Soarers & stuff ... but I dont know how it would go in 4x4 / daily driving.

[Mudderoy]

Hows those new solenoids working out mudderoy ???

Any harshness between gear changes or anything ??

Theres stories that A340 parts are different ... but I suspect the components are just more HD compared to what chrysler provided in the AW4 ??

Some of the ricer websites have mods for solenoid spacers and what not in Toyota Soarers & stuff ... but I dont know how it would go in 4x4 / daily driving.

A little disappointing from the size difference, I can't tell any shifting changes.

[Mudderoy]

I may just being hyper sensitive since I made a hardware change, but the shifts seem to be softer now. Slow acceleration (normal) seems to be like it was before, but the heavy acceleration (normal for me) seems to be softer shift.

P0700 and P0740 CEL codes persist. I'm going to try disconnecting, cleaning and reconnecting the harness to the transmission. Matt has been trying to get me to do this for a couple of days now. :D

[Mudderoy]

So for the last several days (equal to the number that I have had the new solenoids installed) I receive a CEL light after about 3 miles of driving. I get this in the morning on the way to work and in the evening on the way home.

I clear the code and either the TCC solenoid isn't locking the torque converter up, or not all the way.

Anyway I have a definite change in the way the P0740 code is popping up now so I suspect the TCC solenoid has a problem. I mean I only changed the solenoids, the fluid and the filter.

I gave Makco Distributing, LCC a call today. I wanted to see what their policy was on possibly bad parts. I'm still waiting on a call back from "the boss" but I was told that they guarantee the parts to work when they leave their place. But once it's installed they don't normally replace the part.

Wait a minute? It's guaranteed to work when they have it, but not when I have it?

Maybe there's some testing procedure I was supposed to do prior to installing it. I mean I could have applied 12 volts to it and see if it clicked I guess, but does that mean it's working correctly?

I didn't call demanding a refund or a replacement. I just called to see what my options were, perhaps there was even something I could do that would let them know if it was bad or not. I'm not out to screw someone out of money, but well as I said, I need to wait and hear back from "the boss" and see what they are going to do about this, if anything.

The three solenoids were $200, it just seems like a lot of money to me to just roll the dice and hope everything is fine.

[Mudderoy]

Assuming the problem must be the solenoid I ordered another TCC solenoid, but from a different company and one that looked like more of an exact match to the one that came out.

I wasn't very hopeful of my success but I replaced the new TCC solenoid with the NEWER TCC solenoid. Checking the wiring on the old one was tight and looked fine.

If it wasn't for the 19 bolts on the transmission pan this would be really easy.

I went for a long test drive after the change. Absolutely NO torque converter lock up, and no check engine light. I think the computer has a problem with me reading the OBD II data while driving around. So after a good 30 to 45 minute test drive I came home, checked the fluid levels, poked around at a few things, and took it out for another test drive. This time I didn't connect my phone to the OBD II scanner (actively reading data).

I got about as far as I normally do at 50 mph before the check engine light came on. I drove back home and P0700 and P0740.

Things can go bad at any time but I find it damned strange that I went from an occasional P0700 and P0740 and the TCC still locked up, to a P0700 and P0740 EVERYTIME I hit 50 mph for 10 seconds after changing the fluid, filter and solenoids!

Could the other two new solenoids have anything to do with the TCC solenoid?

I'm thinking about dropping the pan again and putting all the old solenoids back and see if the problem changes. Unless someone has a better idea.

As it is I can't drive it back and forth to work because even though the transmission doesn't over heat, it is running hotter. Slipping all the time can't be good for the clutch pads.

[4.3LXJ]

Tony, have you ohmed the old and new solenoids?

[Mudderoy]

Here's a start for ya , it aint pretty but here ya go

http://i837.photobucket.com/albums/zz298/payless4x/po740.gif

Let me know if ya need more

I need more.

[Mudderoy]

http://youtu.be/rskFJ0ujbY8

[4.3LXJ]

Doesn't sound like that TC solenoid is working. Stuck perhaps?

[Mudderoy]

Doesn't sound like that TC solenoid is working. Stuck perhaps?

I have 3 TCC solenoids. One doesn't click, the two others do, but I have to remove positive and negative each time to make them work. Since the 2 NEW ones are doing this either they work that way, or something is causing them to fail.

[4.3LXJ]

I have 3 TCC solenoids. One doesn't click, the two others do, but I have to remove positive and negative each time to make them work. Since the 2 NEW ones are doing this either they work that way, or something is causing them to fail.

I had this same problem on my 4L60E. My solenoids worked, but it wouldn't shift it, and then after 30 min of driving it would shift down into 3rd. I had to get the ohm meter out and found that I had a short in the pressure manifold/sensor. I realize you don't have the same tranny, but the point is that I would suggest that you check everything else for a short of some kind.

[Mudderoy]

Transmission shop says the signal to lock up is being sent to the "stuff" that should lock up. They say they can only tell what is wrong by dropping the transmission and looking. Estimated $1850 for full rebuild etc...

[xj4life2]

If you have signal to the solenoids why would you drop the trans ? I agree with Steve bad solenoid. Call this guy, Darrell at 530-877-1304 he's the best in auto tranny's I've found. Tell him I said to call and he can give you lots of info. Hope this helps ya !!

[Mudderoy]

If you have signal to the solenoids why would you drop the trans ? I agree with Steve bad solenoid. Call this guy, Darrell at 530-877-1304 he's the best in auto tranny's I've found. Tell him I said to call and he can give you lots of info. Hope this helps ya !!

I've installed two new solenoids and the problem didn't change. That was prior to today's test.

[4.3LXJ]

Tony, that is why I am suggesting doing some work with an ohm meter. Pull the plug on the computer and test the pin that works the TCC and test with it plugged in. If it is an open circuit, or very little resistance, then that is your problem.

[LizardRunner]

Hmmmmmmmmm.. now I know why I like my manual tranny so much.

[may pop]

Whats the latest update? Tommorow nite I will be doing this to my new to me 98 2 door. When I got it the CEL was burned out but drove ok. 100 miles trouble. 2 out of three have bad readings at the TCU terminal. You didnt take it in did you. Hope not! Do the solenoids push a plunger? Did you pull them out and wash out the cavity with brake cleen? Just curious what you found.
Ron

[Mudderoy]

Whats the latest update? Tommorow nite I will be doing this to my new to me 98 2 door. When I got it the CEL was burned out but drove ok. 100 miles trouble. 2 out of three have bad readings at the TCU terminal. You didnt take it in did you. Hope not! Do the solenoids push a plunger? Did you pull them out and wash out the cavity with brake cleen? Just curious what you found.
Ron

I don't understand much about the automatic transmission. Frustrating. I may drop the valve body today and clean it. I've already replaced the solenoids without any luck, well actually it went from working most of the time to not working at all after my attempts.

Yes I did take it in and all they did was hook up a scanner to see if the signal was being sent to the TCC solenoid, and it was. Of course all they were able to check from that was that the PCM/TCM was sending the signal, not that it was getting to the solenoid or that the solenoid was engaging.

Basically their FIX was to rebuild and replace.

I don't have any idea what the solenoid is pushing, etc... :(

[may pop]

Thanks for the quick reply. I will see what I can as to the solenoids internal function if possible. If the plunger can be cleaned or not. I should be able to answer monday nite.
Ron

[may pop]

Take a look at the AW4 sticky, The lock up plunger has another plunger inside it. If its stuck it could cause shifting problems. I agree on not knowing whats going on inside the AW4 but every little bit of info helps. I dont believe driving in unlocked mode will kill your trans only raise your fuel consumption or lower your MPG slightly. I will check these plungers tommorow nite and get back with some kind of ancwer if at all possible.
Ron

[Mudderoy]

Take a look at the AW4 sticky, The lock up plunger has another plunger inside it. If its stuck it could cause shifting problems. I agree on not knowing whats going on inside the AW4 but every little bit of info helps. I dont believe driving in unlocked mode will kill your trans only raise your fuel consumption or lower your MPG slightly. I will check these plungers tommorow nite and get back with some kind of ancwer if at all possible.
Ron

Well driving it continually slipping can't help the clutch pads, disks, etc...

[may pop]

The torque converter not locking up [ slipping] is not the same as the trans slipping or clutches slipping like low fluid. Older automatic transmissions did not have a lock up converter. Thats one of the reasons autos got less MPG because of loss due to the converter. That is the reason you noticed a higher fluid temp. due to the converter not locking up. but it isnt putting it into the danger range is it?
Ron

[Mudderoy]

The torque converter not locking up [ slipping] is not the same as the trans slipping or clutches slipping like low fluid. Older automatic transmissions did not have a lock up converter. Thats one of the reasons autos got less MPG because of loss due to the converter. That is the reason you noticed a higher fluid temp. due to the converter not locking up. but it isnt putting it into the danger range is it?
Ron

It's getting close to 220 in the cooler outside temps. I may drive it to work tomorrow, I miss it. :(

[may pop]

Well heres the update.
Monday nite I got home from work and my solenoids were here. I got right to work pulled the pan and could not get the dipstick tube off. The P/O had destroyed the bracket and it was stuck real good. Finally got pan off,swapped out the soenoids straightened the pan and put it all back together.Took it for a test drive and no 1-2. Only manuel shift. Found a broken pin in connector by spark plugs. Went to junk yard got a piece of wiring harness fixed it on Tuesday. Drove like new. All shifts and lock up real nice. STILL HAD 6 CODES. When I was at the junkyard I also grabbed a TCU. So today I put the TCU in and cleared the codes and all stayed away. The low budget TCU saved me alot of headaches.
I got my solenoids from the same outfit in Florida. 2 out of 3 of the old ones were bad electrically and the lockup was missing the plunger inside the solenoid. Seems that 98 was a bad year for the solenoids. Other sites also have lots of guys with trouble on 98s.
Dont give up yet you will eventually figure it out. Get a spare TCU to swap in it could be the fix.
Ron

[Mudderoy]

Well heres the update.
Monday nite I got home from work and my solenoids were here. I got right to work pulled the pan and could not get the dipstick tube off. The P/O had destroyed the bracket and it was stuck real good. Finally got pan off,swapped out the soenoids straightened the pan and put it all back together.Took it for a test drive and no 1-2. Only manuel shift. Found a broken pin in connector by spark plugs. Went to junk yard got a piece of wiring harness fixed it on Tuesday. Drove like new. All shifts and lock up real nice. STILL HAD 6 CODES. When I was at the junkyard I also grabbed a TCU. So today I put the TCU in and cleared the codes and all stayed away. The low budget TCU saved me alot of headaches.
I got my solenoids from the same outfit in Florida. 2 out of 3 of the old ones were bad electrically and the lockup was missing the plunger inside the solenoid. Seems that 98 was a bad year for the solenoids. Other sites also have lots of guys with trouble on 98s.
Dont give up yet you will eventually figure it out. Get a spare TCU to swap in it could be the fix.
Ron

I'll have to have a closer look at my old TCC solenoid. It could be the piece of plunger is missing from it and now it's in the valve body keeping the TCC valve from engaging! :love0055:

[may pop]

Keep lookin your on the right track.
Ron

[Mudderoy]

Started calling other transmission shops.

Dropped it off last night at one near work.

They report low fluid pressure, they are taking it out now.

[cantab27]

not good tony..........im still having trans problems myself...sounds similar to yours.......

[Mudderoy]

not good tony..........im still having trans problems myself...sounds similar to yours.......

Super friendly guy at the tranny shop. I explained to him about this website and I wanted ALL the old parts. I wanted to know exactly what the problem was so I could post here for everyone else having similar issues. Not necessarily the solution for them, but a good possibility.

After some discussion yesterday they are dignosing the problem first, and most likely a full rebuild after the diagnosis. Assuming the full rebuild they will be going with an upgraded torque converter that is heavier and thicker metal that will handle the heat better. Installing a shift kit so that the bands will engage quicker and have less slip, also to have it run cooler.

They will be replacing the accumulator springs with heavier duty ones

I am planning on rebuilding a 4.0 to put in the 1998, so I was a little concerned about putting a NEW motor with increased compression and horse power on a AW4 with 174k miles. So even though I don't like spending the money the replacement engine (in the future) and my right foot probably would have done the AW4 in short order, and it may have been worse than a TCC code.

I saw them pushing a GMC SUV backwards by hand out of a parking spot so they could drive it into one of the bays. No reverse apparently. :D

I asked them to inspect the flexplate closely for cracks, and replace if they found any, along with replacing the transmission mount with a MOOG.

I hate having someone I don't know work on my XJ, especially when I can't watch them do it.

They are shooting to have it completed today.

[4.3LXJ]

Tony, are you going with synthetic oil? Redline makes a really good high temp oil that I am currently running. Supposed to be formulated for heavy use in things like large motor homes.

[Mudderoy]

Tony, are you going with synthetic oil? Redline makes a really good high temp oil that I am currently running. Supposed to be formulated for heavy use in things like large motor homes.

Nope. Dex/Merc. I made it clear to the transmission shop yesterday that was the only fluid I wanted in that transmission and he agreed with me 100%

[Mudderoy]

They checked the flexplate, at my request, and it's fine, however the freeze plug on the read of the engine isnt'! I completely forgot about that freeze plug and I sure am glad they looked at that!

So they'll be replacing the freeze plug for me too.

I wonder what this will do to the pressure of my cooling system...

[Mudderoy]

Low pressure, torque converter bad, clutch plates were worn, flaking, and some were down to the metal.

They were observant enough to see that a freeze plug was bad and very helpful in replacing it (for a reasonable additional fee) however they didn't fill the cooling system up with enough water and promptly over heated the engine during their test drive.

They found the seals were leaking where the transfer case leaver enters the transfer case. They fixed that, resealed it and filled it up with fluid.

All in all I was pretty happy with customer service up until...

I'm talking RPM sticking at 2k rpm, and smoke coming off the top of the engine due to the oil around the valve cover smoking.

This really pissed me off, because there was a guy there sitting in front of the gauges with an expensive scanner paying attention to everything but the coolant temp gauge!

So I had a nice miss all the way home.

I hate HATE taking my vehicles to ANYONE because NO ONE cares about them like I do.

[4.3LXJ]

He didn't overheat it did he?

[Mudderoy]

He didn't overheat it did he?

Sorry I didn't say that clearly in the post, yes it was over heated. Like a dumbass I stood there assuming they knew what they were doing.

It took them a good minute to figure it out and shut it down.

[4.3LXJ]

Not good. You said you had a miss. We aren't talking head gasket are we?

[Mudderoy]

Not good. You said you had a miss. We aren't talking head gasket are we?

That's my fear. They could have damaged the CPS so I'm going to check that first.

[4.3LXJ]

Good luck with that. Did you make a fuss when you saw this happen?

[Mudderoy]

Good luck with that. Did you make a fuss when you saw this happen?

lol yeah. The manager there "Steven" was very nice and helpful, and I tried explaining as nicely as I could that I was very upset that someone sitting in front of the steering wheel couldn't see the engine was over heating. I also told him that it was quite easy for the head to warp on 4.0L and it happened to me when it was two years old. It cost $950 to have it repaired along with an water pump installation (the problem that caused the over heating).

He explained to me that all they did was replace the freeze plug, and I added with then failed to put enough water in the engine, and then failed again to monitor the vitals of the operations of the engine.

When I went ahead and decided to take them up on their offer to replace the thermostat (they didn't think it was low water) they asked me to leave it. I told them hell no, that it was supposed to be read Friday evening and now they wanted to keep it another day. He said "well we close at 1pm".

Customer service goes out the window after quitting time. To be fair they agreed to do it but I needed to go buy the thermostat while they cooled the engine off.

I decided "screw it" I'll just deal with the issue myself. I was hoping that the residual heat in the block was causing it to run hot even though I had filled it up with water.

I was right. It stayed at a hair below 210 all the way home, just had a miss at idle.

[Passt]

Wow that's scary. I know how you feel, I absolutely hate letting people I know know work on my vehicles, for that very reason. You just never know what they're doing / not doing. I'm glad all seems well at least.

[Mudderoy]

While driving home last night (I drive about an hour) I was half way home, came to a stop light and noticed.... the miss was gone!

I suspected that after the engine cooled off it would come back. Started it up this morning, nada. I did notice that I have a slight miss by the time I get to work, and it was the same when I got home last night.

Same noise, same little shack, just much less pronounced than before.

It may be a head leak, or could even be an injector acting up, at least that's what I'm thinking.

[may pop]

But does the trans work great?

[Mudderoy]

But does the trans work great?

Hard to say. I mean any trans should work correctly right after they are done with it, right? With a shift kit and heaver accumulator springs I expected a harder shift. I have to take it back in two weeks. They say they can adjust the shift.

[may pop]

Was it worth the money?

[Mudderoy]

Was it worth the money?

No. In my mind you should be able to replace the transmission with a new one for $300. :spongebob:

[may pop]

My kind of cheap prick!
Ron

[Mudderoy]

My kind of cheap prick!
Ron

I'm just moody because it's one piece that I don't feel comfortable working on. I wish they had said YES when I asked them for a Cherokee with a standard transmission.

[may pop]

To get mine working right ,solenoid filter and gasket,NSS and TCU to clear codes. All told over 440 bucks in a 900 truck.
Ron

[may pop]

My "GENTELMANS JEEP" Has a 5 speed so there is one less problem to have. This will eventually be my DD so an auto trans driving into the city will help stop the aggrevation some. I still say that the solenoids in the 98s are bad. My old 93 which my son is trying to kill never misses a beat,a much better vehicle in my eyes.
Ron

[Mudderoy]

My "GENTELMANS JEEP" Has a 5 speed so there is one less problem to have. This will eventually be my DD so an auto trans driving into the city will help stop the aggrevation some. I still say that the solenoids in the 98s are bad. My old 93 which my son is trying to kill never misses a beat,a much better vehicle in my eyes.
Ron

Well I have two new sets now! One in the tranny one out :D

[may pop]

Save em for the 99.
Ron

[tinythexj]

So I had a 0700 and 0740 code pop up yesterday, the jeep is driving fine with the exception of the CEL being on. Rescanned today and only had the 0700 code. I replaced the solenoids 4 years ago with a set from a 94 and I have a 98, no issues until yesterday. I recently replaced the tranny fluid for regular maintenance so I'm also wondering if I should replace the filter again while I'm replacing the solenoids.

[4.3LXJ]

Never hurts to replace that filter