98 3.8L V-6 from a Camaro

[Sukkoi19]

OK, I installed this motor in a RX-7 about a month ago and I can not get this thing to run right to save my life so I need some help.

It does not trigger the MIL and it has no codes stored in the PCM. The engine will fire up right away and it sounds great then the idle goes to shit. If I hold my hand over the throttle body and cover half of it, it runs somewhat smooth. If I apply throttle, it starts to break up pretty bad. We had a friend come over with a scan tool and the only thing he noticed wrong was it was running VERY lean. He couldn't find anything else.

It is a 98 with a 5-speed trans. I have power everywhere it needs to be and I have a ground everywhere it needs to be. I have tested the MAF, MAP, ECT, IAT, TPS, IAC, both HO2S, I have tested all the sensor reference voltage. I have cleaned the injectors, tested the fuel pump and it's pressure, replaced the regulator. I have replaced all spark plugs and wires as well as tested all of the coils and ignition control module. Everything tested OK. The only things I did not test were the crankshaft position sensor and the camshaft position sensor.

Thoughts?

Thanks for reading the novel.

Jesse

[Superdave]

I had the same problem with my 3400 swap, ended up that i had the MAP on a bad vacuum source.


Check the CPS, should be 980K ohms.. could be degrading or cracked.

[Sukkoi19]

How do you test that? The Chilton said I needed an ociloscope.


Jesse

[glennster]

Sounds like a bad vacum leak or drawing air from somewhere other then the maf.2 things I would look at with a scanner is coolant temp and IAC counts when running.Also a bad maf could cause this,try unplugging it and if it runs good you are golden.

[patriotformula]

...I don't think a MAF could ever be THAT bad. I've had some messed up MAFs over the years and the cars would still run descent.

[Sukkoi19]

The MAF is BRAND new and it tested OK. The MAP is on the factory vacuum source. I have tested for vacuum leaks and have found nothing yet(I still think that is what it is). I am all out of ideas.

Thanks for your input, guys.

Jesse

[Superdave]

admin said:

How do you test that? The Chilton said I needed an ociloscope.


Jesse

you can test it with an O scope but only with the car running, that's just to test the actual signal.

the internal pickup can be tested with a digital multimeter, across the 2 pins is usually around 980K ohms. I've had a few that were lower than that cause timing issues... and a few completely open that would cause no-spark at all.

[Sukkoi19]

Turns out it may have been a vacuum leak after all. My buddy removed the intake manifold and found a really messed up gasket. He will be replacing it tonight to see if that was the problem.

Thanks for everyone's help.

Jesse

[dyers98]

Installer error!

[Sukkoi19]

Bad computer! Fixed as of today!

Jesse