GenVibe - Community for Pontiac Vibe Enthusiasts

This is actually a 2003 Matrix, but sister cars so I hope you can help.

I bought a 2003 Matrix with a blown engine and did a complete rebuild, bearings, rings, reconditioned head, pretty much the works. Kind of stupid to rebuild a 1 ZZ FE, but I never did one before so I figured I’d give it a try.

Warmed up, it purrs like a kitten, but cold starts are hard and it won’t idle until CTS reads 200F. The IAC and CTS are new. MAF is original but I cleaned it and I tested it on another car. Any suggestions to get a good idle are appreciated.

Bill

I believe this model had a recall on the ECM. I'd check first if this recall was performed on your car. A Toyota Dealer can look it up for you.

Look up "Closed Loop" and "Open Loop" for ECM modes of operation. This may help explain why the engine is behaving the way it is. Is the throttle body and intake air system all stock? Was the engine ignition timing checked or verified when the engine is cold and running?

Thanks for the advice.

There is an ECM recall, but it has something to do with the airbag. I don't get it.

It is all stock, TB, air, everything. Timing has been verified.

I just made a rather disconcerting observation. The coolant reservoir is low. My first 1ZZFE might be a big fail.

Bill

As to loop mode, my scan tool can detect this, but I've been so obsessed with CTS, IAC,and MAF that I haven't monitored it.

It certainly would explain why the car can suddenly maintain idle at 190F. I will check this tonight.

If this is the problem, do I need Toyota to flash the ECM (or worse yet replace it)?

Bill

wmdiess wrote:There is an ECM recall, but it has something to do with the airbag. I don't get it.

Hey Bill, there where three recalls for the 03-08 Vibe/Corolla/Matrix: Airbag controller, Airbag inflator, and ECU (main engine computer).

OK, Jolt is on to something.

When I put the key to the "on" position, ECU is in OL mode.

The second it starts, the ECU switches to CL mode, even as the CTS reads 110F.

I have to keep my foot on the pedal until CTS reads 190F, then it will idle on its own.

SeattleJeremy wrote: Hey Bill, there where three recalls for the 03-08 Vibe/Corolla/Matrix: Airbag controller, Airbag inflator, and ECU (main engine computer).

If I remember the ECU recall was about idle speed problems at stop lights. I do not recall if it was to fast or to slow, but most dealers replaced the ECU, $$$. Then again, you may have already had the recall done. You may be able to check on line with your cars VIN number to see if there are any out standing recalls on that vehicle.

When you did the timing check, you used a timing light? Most cars require pins in a connector to be jumped to remove the ECU from the timing check. If the static timing is retarded, the idle speed will be slow until the engine warms up and the ECU takes over. The open and closed loop have to do with when the ECU takes over adjusting things on the engine. None of this has to do with a port reader.