Hey I have a problem. I had a CEL for a cat, so I replaced it. I just had a full tune up, including spark plugs, fuel filter, throttle cleaning and injector flush. So I trhough after all of this is would have gone away. I am not sure how to describe it but it is when I step on it (WOT) and the engine chugs/sputters as it accelerates. The best example of it was at like 50mph i put it in fifth and floored it and oh my did it ever start chugging (hesitating). Do any off you know what this could be. Oh yeah I just cleaned my air filter also and there is no CEL light on. Thanks for the help
Symptoms got worse after the tuneup ?
Sometimes you can get a bad set of new spark plugs....
It's happened to me many times....
Currently running E3 Diamond Fires....
Best plugs in my opinion....
No they didn't get worse they just didn't go away. I have the ECO and I put in the recommended plugs which are the platinum 4's
Under high compression plugs tend to "flame out"....
Do you now suspect the coils are getting weak
and not "throwing enough" ? ....
I would get a fuel pressure test done, Maybe youre fuel regular is weak or Coil packs are weak,
Is there a way to test this myself or should I take it to a mechanic
Check for water in your fuel. I had it happen 2 times, you'll have to empty ur tanks contents into a jug, and check for 2 seperate fluids. One will be water, one will be fuel. The water will not ignite
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Most likely your prob bud.
Not criticising here, but why are you putting your car in top gear and going WOT? This puts a HUGE load on the engine.
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"The Blue Bullet"
I am leaning towards fuel pump or spark plugs
I am having the same problem with the hesitation. It's intermitent. But it feels like the car has lost power since the problem. I have a 05 Cav. Replaced the plugs and air filter. Oil change. I believe the problem started when my MAF sensor went. I had the dealer fix it but now this problem is getting worse. It's in any gear. The best way to describe it is, When i step on the gas it hesitates for a good 4 seconds then it kicks in really hardcore. when this is happening i can just leave it in neutral and rev it and it sounds sluggish almost like not all 4 cylinders are firing. Any help with this would be great.
Update,. So today was extremely hot. On my way to work my car started acting wierd again. And then the check engine light came on. Drove to auto zone and got it checked at apparently it was DTC P0172 Fuel Trim System Rich Bank 1
Actually, that code is thrown when bank 2 is too rich. So I'd say it's one of these 2:
Your fuel pressure regulator (FPR) may be suffering from a leak. Make sure to have it looked at and that the area that bank 2 is running through is functioning properly.
Your PCM is getting the wrong readings. I'd check out your sensors (oxygen sensor would be the first place to look) and make sure they are working right.
Good luck!
Hey, the other day i took my idi cover off to paint it, and when i put it back on, i started gettin this exact problem, its a 98 LD9, is there somethin i might have @!#$ up when takin the idi off and putting it back on?
My car had this problem... I thought it was a vacuum issue. (No CEL lights though) Ran the car up, and was looking/listening for vacuum leaks. then i heard the sound of an electrical snap. I revved the engine, and about every 3-6 seconds or so I noticed a spark going from the ignition coil on one of the terminals, to the bolt holding the coil onto the block. Replaced the coil, problem seems solved.
hmmm, so sounds like it could be a coil, or a spark plug, or anything inbetween