Car Only Runs When Starter Is Engaged

[Gary Stanton]

I just did a 5.0 manual swap on my 1993 4-cylinder automatic lx mustang. I bout a 1993 5.0 wiring harness and a A9L computer. I have everything hooked up and when I start it as soon as I let the key switch back into the run position it dies. Any ideas on how to fix this problem?

 

[Noobz347]

It SOUNDS like you have an ignition switch problem at first glance. There's not a whole lot of information to go on in your post.

Have you tried pulling KOEO codes yet?

 

[Gary Stanton]

It's starts first hit and sounds good but it won't stay running unless the starter is kicking in I've checked the solenoid and the coil they are fine the battery is good to and when I did the swap I didn't get the harness for the t5 manual I just spliced the two wires together so it would start with the key.

 

[mikestang63]

Randomly jumping wires is not a good thing. You need to have the correct harness or you will be chasing down gremlins or worse burn your car down.

 

[Gary Stanton]

Also when I switch the car on the fuel pump doesn't kick but it pumps fuel when It turns over.

 

[Noobz347]

It still sounds like either an ignition switch problem or a wiring problem.

Let's holler out to @jrichker . He's our resident wiring guru and probably has a simplified schematic and troubleshooting tips lying around that can help you.

 

[Gary Stanton]

I just turned the key to the run position and bumped it with the screw driver but it did the same thing..it runs and idles just fine long as long as the starters turning but I took the screw driver off and it dies

 

[Noobz347]

Look to ensure the wiring to your starter solenoid is correct.

COURTESY OF JRICHKER

 

[Gary Stanton]

It runs..I feel like an idiot thanks guys for the help!!

 

[mikestang63]

what was the problem?

 

[jrichker]

From the "Cranks OK, but No Start Checklist for Fuel Injected Mustangs"

Paragraph 1, item K....

K.) Engine fires briefly, but dies immediately when the key is released to the Run position. Crank the engine & when it fires off, pull the small push on connector (red/blue wire) off the starter relay (Looks like it is stuck on a screw). Hold the switch in the crank position: if it continues to run there is a problem with either the ignition switch or TFI module. Check for 12 volts at the red/green wire on the coil with the switch in the Run position. Good 12 volts, then replace the TFI. No 12 volts, replace the ignition switch or the fuse link in the red/green wire.

Notice the fuse link in the ignition circuit below...
Diagram courtesy of Tmoss & Stang&2birds

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

 

[Noobz347]

what was the problem?

The world may never know.

 

[Gary Stanton]

Ok new problem with my 5.0 it starts fine and idles ok but when I get in the the gas it spits ,sputters and backfires. And when I drive and barley give it has it's fine but if I get on it , it's like I'm riding a bull.any ideas ?

 

[Noobz347]

Ok new problem with my 5.0 it starts fine and idles ok but when I get in the the gas it spits ,sputters and backfires. And when I drive and barley give it has it's fine but if I get on it , it's like I'm riding a bull.any ideas ?

No more help until you tell what the LAST fix was.

 

[madspeed]

Ok new problem with my 5.0 it starts fine and idles ok but when I get in the the gas it spits ,sputters and backfires. And when I drive and barley give it has it's fine but if I get on it , it's like I'm riding a bull.any ideas ?

yep, you messed something up

 

[Gary Stanton]

I had the wires on the solenoid backwards()

 

[madspeed]

how about he sputterng? you forget to plug in your maf?

 

[Noobz347]

I had the wires on the solenoid backwards()

I mean... uhermmm... was that so hard?


Ok... next problem. Check your timing with a light first. Should be set to around 12*.
Pull KOER codes. If no codes go to next.
If that checks out, just swap the TPS sensor. Yes... you can check it with a DVM but they're so cheap, it's just as easy to swap it out.

 

[Gary Stanton]

I'm running a edelbrock performer rpm intake on it could the vacuum lines be cause the problem

 

[Gary Stanton]

The timing is set two marks after top dead center.