Nagging Hot Start Issue

[HawleyFoxHatch]

Help! I am having a hot start issue. I have seen multiple forums and checked/replaced recommended "problem parts". If I cut the car off after after 180°, no start. Wait 5-10 mins, starts up. No problem with cold start. Holding the pedal to the floor, nothing different. ** When this happens, I do not hear the pump prime**

New Fuel Pump
New IAC
New coolant sensor
New bap sensor
New Distributor w/ignition module
New Starter
Swapped out ECU
Checked grounds & added more grounds
No Codes

 

[Dan02gt]

Being that you don't hear the fuel pump, have you checked the fuel pump relay? If not that's where I would start.

Here's a link to the cranks but doesn't start check list. Run it up to 180* to replicate the issue the try this:

https://www.stangnet.com/mustang-fo...-checklist-for-fuel-injected-mustangs.787471/

 

[mikestang63]

you changed everything but the most common cause for hot start problems.. the TFI
As stated run the codes

 

[HawleyFoxHatch]

That's new. I failed to list that.

 

[mikestang63]

That's new. I failed to list that.

did you use a genuine FOMOCO unit and grease the back of it before install

 

[HawleyFoxHatch]

It was attached to the new distributor already. The problem existed prior to installing the new unit. I was sure that or the pip sensor was the culprit so I purchased the whole thing.

 

[Mustang5L5]

What year is the car? Have you checked fuel pump relay?

 

[HawleyFoxHatch]

What year is the car? Have you checked fuel pump relay?

I'm heading to grab one shortly. I just noticed this evening the pump was not priming during the hot start condition.

 

[Colton Howell]

I had the same problem in my 1987 fox. I replaced the fuel filter and it was filthy. Ever since the car has run stronger than ever. I replaced it about 4 months ago. Try this if you haven't already it helped me out and I have made numerous long trips with no problems since.

 

[HawleyFoxHatch]

My fuel filter is new. I replaced the Fuel Pump Relay. I will take it for a test drive tomorrow. It was in bad condition so hopefully that was it. To be continued....

 

[HawleyFoxHatch]

Update: Fixed. It must have been the bad connection (possible other contributing factors) on the fuel pump relay. The previous owner attempted to repair the stock wires off of the pigtail. The parts that were replaced probably needed to be anyways. Thanks for the help guys!