6G Celicas Forums

I am having some problems with my 7afe whenever I got around 2,000 Rpm it starts sounding like gas would be cutting off then it runs normal when I press the gas pedal? And another problem is when I first turn it on before it heats up it runs normal and smooth once it meets it's normal temp it feels very slow and loses power can't think if anything that it could be Thanks

what year is it? any Check Engine Light? I need more information.

It is a 1996 st and yes theres been an check engine light

http://www.6gc.net/howto/determine_check_engine_light_codes

There is a lot of useful, information in the stickies, Ive read them all at least thrice

Sounds like you have stumbling/misfire/something's up in open loop.

Thanks I'll check them out


How would I fix that?

A lot of various issues, tough to diagnose. Can include a vacuum leak(s), faulty air sensors, exhaust leak, fouled spark plugs, bad fuel pump...

Important that you get somebody to read the ODB code that is driving your CHECK ENGINE light before you do anything else.

I am going to guess that it has something to do with your EGR (exhaust gas recirculation) system, the emissions control system that prevents the creation of NOX, nitrogen oxide gases. NOX causes acid rain. I wrote a lengthy discussion and saved it to a Word file until I know what ODB code you find. If it pertains to the EGR, then I have some information to help you.

The only way the egr can cause a misfire is via a vacuum leak in the hoses controlling it or for the egr valve to be physically stuck open. Its highly unlikely it would stick open, they always fail and throw an insufficient flow code, its inherent to the design that 99.9% of the time they fail closed. If the egr failed it would impact the engine most at idle, not at 2000 rpm. But it would just make the engine run better if it failed, not worse, while slightly increasing NO2 emissions.

Check the code first, just short a wire or paperclip between E1 and TE1 I believe in the diagnostic port next to the master cylinder in the top driverside of the engine compartment. Then turn the key on and count the number of blinks. It will flash several times(first digit X_), pause and then flash several more times (second digit _X). It may pause a long time and then start flashing another code.
Flash - flash - - - - - flash - flash - flash - - - - - - - - - - - - - flash - flash - flash - - - - - flash - - - - - - - - - - - - - - repeat.
^this would be a code 23 and code 31 for example.

Try it out and let us know what you find.

Glad to have found someone who understands the EGR system. FYI: I am one of the unfortunate 99.9% that has an EGR code different from "insufficient flow." At the present time my 2000 Tacoma has a code that translates to "excess flow," which indicates that my EGR valve might be stuck upon, and I've tried cleaning the EGR valve, but since that didn't change anything, I deferred digging too far into the problem until I get my Celica back in service. My personal research says that you are correct in everything you are saying in this comment, and I am glad you provided a way for him to check his code. That should come first. With an "excess flow" code, my truck engine performs just like it always did, from idle to speed.

The Haynes manual for my truck shows EGR system diagrams for 93 to 95 V6 3.0 L engines. It has a table that shows what parameters the ECU is looking for, and includes the coolant temp, VSV state, EGR valve pressure, and throttle position (how far open). YouTube videos are in line with what you are saying, since there is no video that addresses "excess flow." Many of the "insufficient flow" codes show up as a lot of carbon build up in the internal channel leading to the input manifold. The YouTube videos also show how the EGR can cause a rough engine. In one case a certain diagnostic procedure will cause the engine to stall (or come close), or not, depending on the problem when testing, so an EGR problem can effect the running of the engine. EGR problems fall at the interface between auto mechanics and the on board computer (a black box to DIY people). The ODB tool information emphasizes that you should diagnose a problem rather than trying to solve by replacing parts; frequently you will replace a part that isn't bad using that approach.