hi... for the past few weeks my car has been acting strange on acceleration, it would give me a jerk like as if the car was loosing power and then it would throw a check engine light for a quick second and then the check engine light goes off and car runs normal again, but at times if the car would jerk very bad or multiple times it would stall. So I had my fuel pump replaced today and it seems like its a little better, but not 100 Percent, I have noticed it not jerking as bad, and not stalling, but still throwing a quick check engine light then the light turns off, and it is still having a slight loss of power and jerk on acceleration, what should be my next step? I have checked for codes but nothing comes up! Any help would be appriciated, thanks so much!

 

Was the fuel filter replaced at the same time, if NOT, do so. If unsure, change it, it is cheap, and reeks havoc if clogged.

Possibly the O2 sensors are having a dying moment, seems to be raising its ugly head more and more, as these cars age.

Dirty throttle body/disc as the black goo affects air flow and idle mainly, but it does require regular cleaning and may not have been done for a long time.

Blocked exhaust sytem.

Octane of fuel too low, knock sensors retarding the engine system.

Spark plugs are due for change.

Try some injector cleaner in the fuel tank after the filter renew, and make sure you only run "premium" octane fuel. Down here that is 98, and my AJ16 is sweeeeet using it, and only so so on the 95 recommended by comparison.

 

hi francis, thanks for the info, I did the fuel filter on the last oil change about 3 months ago... Havent checked the 02 sensors yet, but a Jaguar tech told me that a check engine light would stay on if they were going bad. I cleaned the throttle body a few months ago because it was sticking. I changed my exaust system out about 2 years ago, but if it is blocked, how can I clean it out?? I only run Premium in the car, and have pourned in a gas cleaner but didnt help. Anything else??

 

OK, that cleared the head somewhat.

TPS, (throttle position sensor) is now ringing fairly loud and clear.

It is under the throttle body, and body removal is required to replace it.

That "goo" we all talk about runs down the throttle shaft, something to do with gravity, and runs inside the TPS. Sometimes a GOOD clean out with solvent cleaner, I used carby cleaner on mine, and you may be blessed by whoever and it works, or you might just kill it totally.

You guys up there get an EGR system, we dont, so maybe that is having a hissy moment and causing the issue. Someone in your part of the world should have more info on that system and how to repair/clean/test its operation.

The exhaust is maybe OK, it just appeared on my radar due to the age of these cars, and some posts that have had exhaust issues??, and subsequent running issues.