PROBLEM: during cold start, at around 2500 rpms, the car sputters and misses badly, like a loss of power, when slowly revved, it misses bad and the check engine light blinks, if i just floor it, it does fine. after warm up, it rides perfect on the road, heres the weird part, if i push the clutch in, and rev it, it does terribly, even after warm up.

NOTE: just did a swap, and it ran fine before the swap, the problem im having has gotten better since i first cranked it after the swap, im thinking secondary fuel injectors, weather they are clogged, or the newly (used) ecu is not working right, (how do u know if an ecu is bad?) i dont know. i have only a gutted downpipe, and BOV, i put new wires and plugs in the car, and a new air filter, and extra grounds, any ideas? any thing i should check? what does this sound like to yall?

thanks, paul

 

bizzump

 

come on now

 

anyone have a clue?

 

You cannot push your car until it is warmed up!
I cannot stress this enough.
make sure you warm up the car before you drive it or be very very gentle until it is fully warmed.
I believe I have read that the stock computer doesn't let the engine use the boost until it is warm, so it will seem a lot slower until then.
I think the computer goes into a warm up mode until warm and the car will seem "crippled" until fully warmed.

When you rev the car up in neutral while it is warm what does it do thats weird??
Does it rev up normally then when you let off the RPM's fall inconsistantly?? or seem to catch on the way down to idle??

But remember to please warm the car up all the way before giving it gas PLEASE
Justus

 

The stock ECU does either limit boost or retard timing during warmup...I forget which....but nothing drastic like was described here. The sharp bucking sounds a lot like the infamous 3K hesitation, but I've never seen that cause a check engine light, and I've never heard of it happening after the car is warm.

jds

 

yeah the bucking happens around 2500 rpms, and if im revving really slow, it just stays theres, and bucks and cuts out, never quits, and during all this the check engine light is blinking, but if i floor it, it than rev normally, and it does it worse when i have the clutch pedal pressed in, and i do let my car warm up before i give her heck. i have put extra grounds in for the 3000 rpm hesistation, and that took care of that about a month ago.

does anyone else have a clue, is there anyway to check if an ecu is bad.

anybody!?

help!

thanks though,

paul

 

hola?

 

anyone?

 

hello

 

Run the diagnostic and check for an engine code.

-Charlie

 

already did, no codes, light just comes on, than goes off during the sputtering, thanks though, anyone else?

 

Have you tried resetting your ECU? That sounds sort of similar to limp mode.

-Charlie

 

i agree it does sound like a limb mode, i have reset that ecu about a million times, i have another computer on the way, but in the mean time, anyone else got any idea?

 

bump

 

anyone else?

 

ok heres a few concrete things it can be.Your injectors are leaking causing flooding hence the bucking.Your ignition coils are bad which is more likely your problem or your boost sensor which is right next to your brake booster has a leak in the hose.
How do i know this?
Same **** happened to my car.
except now my car is worse off.The engine now floods out.It used to buck under light throttle but under heavy load it would stop.Sounds like you are having the same problem.
First thing you should do is change your fuel filter and run some injector cleaner.Also if you can test your ingnition coil packs.If your coils are fine its most likely your injectors are finally going out and leaking.Good luck.
Ohh yeah check the boost sensor ,if it becomes disconnected from the vacuum line ,car runs like **** and lots of white smoke.hence a vacuum leak.