07 Corolla LE - RPM fluctuating, No start

[mehiar427]

Hello all, I'd like to first off thank anyone who reads this and can provide some input on a little problem I'm currently having.

2007 Toyota Corolla LE 1.8L

Problem:
-Vehicle does not start unless force is applied to the key when turning it on.
-Vehicle will not start again after the vehicle has warmed up after turning it off.
-RPM fluctuates very noticeably; customer had TPS sensor changed, did not fix the issue.


I had a customer come in today with a no start condition on his Corolla. He told me he had a shade-tree mechanic change his TPS sensor due to his vehicle fluctuating RPM while it is at idle. I verified the no start condition. Weird thing is, I applied some pressure on the ignition switch (pushing harder on the key while turning) and it cranked right up. Possible bad ignition module?

Anyways, after the vehicle was started I instantly noticed the fluctuating RPM that apparently the TPS did not fix. It idles anywhere between 500 and up to 2000 RPM, then begins to feel like it's dying. When I accelerate it, I can not get it to go past 3000 RPM, and when the accelerator is released, the car feels like it's going to die.

Any ideas on some things I need to check on? Could the mechanic he sent it to for the TPS replacement done something?

Thanks in advance for some helpful insight.

[mikered30]

Any codes at all? Sounds like the MAF could be faulty or dirty? Coils test ok? Are all vacuum lines connected properly and cant imagine the throttle body is that dirty already, but it is worth a shot to check it out.

[dorman68]

I had an idle fluctuation issue and it ended up being a bad intake manifold gasket. The gasket caused a vacuum leak by the cylinder head area causing the engine to idle erratic.

[tigerclaws1318]

Could be a bad ECU. There's a TSB about it going bad causing the car to lose power and die unexpected.
It's best to let the dealer deal with it.