bennybenster

How do I test if ECM is bad or not?

AdderMk2

swap it out with a known good unit...

bennybenster

I finally got back to working on my car again. I cut my finger pretty bad when I was trying to removed the old ECM and it took me a few months to get myself back to working on it. I've replaced the ECM with a new one and the car still does not want to start. I'm going to go through the "How to Solve an EFI No Start" guide again to see if everything still checks out.

Any other tips for me?

redpony88

try a new coil. they arent expensive like 45 bucks for a msd one. i went through this before with 86whiteponys car, we put a new tfi in, new fuel reg, fuel pump, filter and it turned out to be the coil..... plugged in the other coil and it fired right up

bennybenster

Just installed new coil and still no start.

brentloftis

I have to ask, I know you said you went through the no start procedure but before you mentioned you did not have any spark, is that still accurate? If so you need to check the wiring going to the coil. Also curious if you hear the fuel pump come on and that you have fuel in the rail. I see you mentioned that you tried spray start (startingfluid) well carb cleaner but anyway..... where did you spray it, hopefully in the in the intake(large opening with the CAI off) and not through the hoses in the previous pics.

redpony88

hmmm, make Sure you hear the fuel pump coming on, then while the keys on try just pressing on the schrader valve, it's on the fuel rail, looks kinda like a valve on your tires, if gas squirts out you at least know you have pressure up to that point, however the injectors may not be pulsing, so you could try a noid light to see if they are working. if it's not getting fire it should reek of gas. and you know the ecu you replaced is a fully functioning one right? despite whats been said, try a new maf sensor. i've heard more ofter that the car wont start or run without it. i know my friends 02 just Died when the maf came undone. i havent personally tried to see if mine wont start without it. but it may have killed the maf and maybe they really wont run without it. dont quote me though lol.

86whitepony

yep ^^^^ that's true the 02 would crank up then instantly die with out the maf, didn't sensor any air coming through so it bogged down and died until i fixed the leak in the cai kit unit

bennybenster

brentloftis - I need to go through the steps again and I'll verify that no spark is still accurate. I do hear the fuel pump come on. When you say "check the wiring going to the coil", what do you mean? If I go through the no spark procedure, would that satisfy that statement? And I sprayed the carb cleaner in the throttle body with the CAI off.

redpony88 - I'll give those fuel tips a try. The ECU I installed is new (well I think remanufactured) from Checkers and without any way of testing it out myself,I'm going to assume it's good.

I've been trying to start the car without the MAF on because I was under the impression that the car should start without it on (from other posts). I'll put it back on and see what happens.

Question - If I have to buy a new MAF, can I buy ones for 24lb injectors and get the injectors later? Or does it have to be ones for 19 lb injectors? I'd hate to buy a new MAF now and have to buy another one again when it's time to get 24 lb injectors.

redpony88

well today i pulled my intake tube off cause i was cleaning my iac out to help my idle out but thats beside the point. while i had that all off as in my maf wasnt there , i remembered this post and decided to give it a shot to see if it'd start up and the car wouldnt start up at all. you can get a c&l maf housing anf get a new sensor elsewhere, but the c7l has tubes you can pull and swap out to change the ammout it samples. i had one on my fox i put in 30 lbs and got the calibrating tube for 30's. but the maf would be where i would focus