Delayed start when cold (first start in Morning)

JEREMY NEEDS CAR

MEMBER
1991 FORD TEMPO
2.3L
4 CYL
2WD
AUTOMATIC
80,000 MILES

Turns over for several minutes until fuel pump relay near glove box clicks (check engine light shuts off) then starts and runs good. Restarts and runs fine until it is cooled down and off for several hours.
I replaced the Main ECM
I replaced the fuel pump relay
still will not start right up cold

I am dumb founded with my Tempo problem. I may replace the coolant Temp sensor but it would have to be an in series circuit with fuel relay or something (if it is culprit). I just can not find any info on this symptom. I just hope there is a Ford Tech from the early 90's that can let me know what is preventing Fuel pump relay from not activating immediately in during cold start condition. Replaced main ECM and fuel pump relay.

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
47,567 POSTS

Yes you should replace the engine coolant temperature sensor becasue that is what I was going to suggest when reading your post. Here is a guide to show you what you are in for when doing the job.

https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

Here is the location for your car (Below)

Check out the diagrams (Below)

Let us know what happens and please upload pictures or videos of the problem.

Cheers, Ken

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