I've had lots of repairs done to my car and now while stopped at a light it will kind of stutter, but not stall. The RPMs will drop about 25 or a little more. The CEL came on. This are all new after the shop did the repairs they also got codes for EGR, catalytic converters. The converters, which are about two months old, were replaced because the car barely failed emissions. After replacement the car barely passed.

The shop tried who knows what but they kept getting a CEL. They replaced the EGR valve. Today I took it out on the freeway for about 30 miles to make sure it heated up. It ran like a champ. After letting it set for about three hours I took it around town through stop lights. After a few miles I stopped at a light and it stuttered again. A couple of miles later it started doing it 2-3 times at a light. Running it's just fine and I do not have a CEL on. Tomorrow I'll take it out again.

Have any idea what's going on and why it would stutter and the RPMs drop?

The repairs:

I was losing a lot of oil. I'm also not one to put 19 year old parts back in, and since they were tearing it apart, I had a lot done. In no order here is what all I had done:

EGR valve
oil filter
oil
wheel bearing kits
tie rod ends
ball joints
belt
valve cover gasket
rear main seal
water pump
rack and pinion
trans seal
motor mount trans mount
coil boots
spark plugs
spark plug tube seals
power steering pump
power steering hoses

 

Have you sprayed cleaner in the throttle body or changed the fuel filter? Have you put a fuel gauge on the fuel rail to measure the pressure? Have you cleaned the corrosion of the positive clamps off of the fuse boxes?
Just trying to think of some easy free things to help smooth to out....?

Let me know...jake

 

Since the CEL came on there will hopefully be a trouble code stored....which might prove helpful. In any case, that's where you should begin.

Misfire/stuttering at idle is a somewhat common issue on these cars and, sorry to say, not always easy to solve. Over the years I've had the problem at least three times that I can remember.....but I've had a such a slew of driveability issues that some of the episodes are running together in my memory.

A few years ago I had a stuttering-almost-stalls-at-idle problem that was solved by replacing the crankshaft position sensor. That was a $100 shot in the dark that worked out for me.

A couple times the same symptom was caused by an ignition coil beginning to fail.

Most recently (15 months ago or so) I battled a misfire-at-idle problem for weeks (long story, filled with misery and torment, I won't bore you with it here). On nothing more than whimsy I replaced the plugs...and the problem went away. The existing plugs were only 6 months old and looked perfect. I have no explanation.

Others have reported chaffed coil wiring causing a misfire. Others still report corroded ECU pins causing misfires.

Checking/cleaning/tightening all relevant connections and grounds is never a bad idea. A bit time consuming but sometimes it pays off.

Cheers
DD

 

What did you do with the old power steering pump, water pump and the rack and pinion?

 

The old parts went as cores. I have a friend who works for ATS here is town. When asked if he could get me rebuilds he said they haven't had a core since last November.

 

I'm not doing the work. What I had done is way over my head. My trusted indy is doing it.

Have they checked the fuel pressure I don't know. I don't think they cleaned the throttle body or changed the fuel filter as they are not on the bill. With my indy smalls like changing a fuel filter not being on the bill does not mean they didn't do it.

 

A few things. I was thinking plugs or coils as this didn't start until after the plugs. That raises the question, would they cause EGR codes?

If it was a crankshaft sensor wouldn't that have its own code?

As far as the stall goes, I don't know if there is not a good better word than stall. To me stall is a deeper, more powerful, drop. It's no where close to shutting down the car. My RPMs drop <50.

I will discuss these ideas, and any others I get, with them tomorrow.

 

An issue known to cause stalling on Jags is low transmission fluid, so it would be worth checking the level is correct while hot and to ensure the fluid is clean and bright red.

Since CPS issues can be difficult to diagnose until complete failure, if your CPS is more than 5 years old it would be worth replacing it preemptively and storing the original in your trunk as an emergency spare.

Cheers,

Don

 

Suffering from CRS today. What is CPS?

 

New idea. Took her out today. Still no CEL. While not as bad as yesterday it still stalled a couple of times.

Today I noticed a couple of things. First sitting the RPMs fluctuate a little.

Second I tried it with the AC off, while I could stand the heat. It didn't do it even once with the AC off.

 

Don

Thanks for the suggestion on the transmission fluid. While it was very red and clean it was also way OVER full. It is filled all the way to the "S" curve in the stick.

I don't know if that would cause my problem but I'll get the extra out tomorrow. What other problems would this be causing?

 

Did you check the fluid with the engine running? If not, it will read over full.

 

YES, over-full transmission fluid can cause problems, so please do remove the excess and report back. If I'm not mistaken, in an over-full transmission the torque converter may not be able to fully disengage, so the engine is subject to partial resistance that causes stumbling. That may not be an accurate technical explanation, but there is a reason we are instructed to never over-fill the transmission.

Check your owner's manual for the correct procedure for checking the level - it's sometimes different depending on the model and year. On our '93, for example, you drive the car until the transmission fluid is hot, park on a level surface, depress the brake pedal and shift through all the gears, including reverse, staying in each gear long enough for the transmission to fully engage in that gear. Then put the transmission in Park and wait one minute (our transmission fluid dipstick actually reads, "WAIT ONE MINUTE"). Now withdraw the dipstick, wipe it clean, fully reinsert it and slowly withdraw it and read the fluid level. If there is excess fluid on the gauge, wipe it clean and repeat until you get a clear reading on the dipstick gauge.

For the transmissions in most of the vehicles we have owned, the HOT reading was always more important than the COLD reading.

Your manual may instruct a different procedure, so don't follow the above sequence without consulting the correct procedure for your model and year.

Cheers,

Don

 

CPS (or CKPS) on later cars is the abbreviation for the Crankshaft Position Sensor, a very important sensor mounted near the crankshaft on the front of the engine. The Engine Control Module uses the signal from the CPS to establish correct ignition timing, and a failed or failing CPS often does not trigger a CEL or DTC (Diagnostic Trouble Code).

Cheers,

Don

 

[QUOTE=Don B;932992]YES, over-full transmission fluid can cause problems, so please do remove the excess and report back. If I'm not mistaken, in an over-full transmission the torque converter may not be able to fully disengage, so the engine is subject to partial resistance that causes stumbling. That may not be an accurate technical explanation, but there is a reason we are instructed to never over-fill the transmission.

Check your owner's manual for the correct procedure for checking the level - it's sometimes different depending on the model and year. On our '93, for example, you drive the car until the transmission fluid is hot, park on a level surface, depress the brake pedal and shift through all the gears, including reverse, staying in each gear long enough for the transmission to fully engage in that gear. Then put the transmission in Park and wait one minute (our transmission fluid dipstick actually reads, "WAIT ONE MINUTE"). Now withdraw the dipstick, wipe it clean, fully reinsert it and slowly withdraw it and read the fluid level. If there is excess fluid on the gauge, wipe it clean and repeat until you get a clear reading on the dipstick gauge.

For the transmissions in most of the vehicles we have owned, the HOT reading was always more important than the COLD reading.

Your manual may instruct a different procedure, so don't follow the above sequence without consulting the correct procedure for your model and year.

Cheers,

Don[/QUOTE

I've never over filled one before and I didn't do this one. This is the only car I've had that didn't have the directions on the stick. This one just has a hot range.

I checked it hot and running in Park, neutral, and off. Either way it was still way over full.

The one thing I've never had with this car is the manual. That one reason I love the Internet.