Uniflightstang

Hey guys. I need help from you stang experts out there. My 91 LX just refuses to start.
Here is what I have done to troubleshoot the problem in steps of course:

-Verified spark....all cylinders good
-Verified fuel...all plugs new and wet
-Replaced TFI module in distributor
-Verified all engine compartment connections are connected
-Verified mass air sensor good with another new one I have
-Verified TPS sensor idle and WOT voltage
-Replaced battery with brand new Optima
-Replaced Cap, Rotor, and Coil

I was going to spray this car for a while while my stroker motor is being built.
The car cranks but wont light off. The only thing left to replace would be the plug wires and the IAC sensor. Any help would be greatly appreciated. Thanks.

Tony71502

Plug wires have nothin to do with the problem.

Are you positive that you have spark in every plug? If you have spark and fuel in each cylinder. Id be willing to bet that your dizzy is backwards. Making your motor completely out of time. But if you didnt touch your dizzy since you have last fired up the car, then thats ruled out.

If its not the dizzy, maybe your lacking compression(do a compression test?) or maybe you are extremely lean or rich. Is it possible to bypass the IAC by opening the throttle?

fourfivefour

You must be missing something, fuel and spark it should at least try to fire.

Uniflightstang

Yeah. I knew the wires were not the issue. Dizzy has not been removed since it last run. I failed to mention this. About a week ago the car backfired out the upper intake. I think it did because I had the TPS sensor voltage way too high. So maybe the timing chain jumped. Next thing will be to verifly TDC on #1. If its off then it looks like Im replacing the timing chain.

Joel5.0

FYI..... How to Solve an EFI NO START

Uniflightstang

Update. Verified TDC #1 and the timing. Its correct. But still refuses to start. Could it be my IAC valve? I figured if that was bad it would just idle like crap. The car still refuses to start. I bought a Prof Products Throttle body and EGR spacer off of ebay. Has anyone had problems with these things. I know they are cheap and you get what you pay for. Just wanted to know..thanks.

mjr46

so you are basing you got fuel by saying the plugs are wet??.....#1 when you turn the key on can you hear the pump in the tank run for a few sec??? then go off??....did you check for fuel pressure with the proper tester?? = hooked to the fuel rail......also you have verified spark via a inline spark checker right??? when you spray ether in the intake will it fire up briefly??? also do you have injector pulse..and a IAC motor has nothing to do with your problem save your money for now

mjr46

also why not follow joel5.0's link and instructions....

Uniflightstang

This all started after it backfired out the upper intake because of a way too high TPS voltage. It hasnt started since. There are no bad mechanical sounds coming from the engine. So I dont think i harmed anything from that. So the question would be. What sensors could I kill from the backfire out the upper intake? How about the MAP sensor or something like that? I will try a little ether tonight. MJR46 thanks again for the help.

DrmZero

sounds like you fried the ecu