Ford 1993 F-150 5.0L engine

DAVEHUSBAND

MEMBER
1993 FORD F-150

Truck wont start unless you put a couple of drops of gas down the throttle body. Will run fine all day after that but when you turn it off again it wont start unless you repeat the process. Got spark and good fuel pressure kinda stumped ask mechanics around here but no luck.

Friday, January 5th, 2007 AT 10:49 PM

4 Replies

CARUNDELL

MECHANIC
602 POSTS

Hey dave,
Interesting issue! Is the check engine light on? Does it tend to "smell funny" out the tail pipe? Let us know!

Chris

Was this

answer

helpful?

Yes

No

Saturday, January 6th, 2007 AT 4:20 AM

DAVEHUSBAND

MEMBER
2 POSTS

Hey well its not my truck my brother in laws he said hes check engine light is on but because he had to unplug his thermostat sensor cause it was idleing high. We went and asked all the mechanics at the ford dealerships and they didnt even know.

Was this

answer

helpful?

Yes

No

Saturday, January 6th, 2007 AT 4:20 PM

TAURUSWHEEL

MECHANIC
718 POSTS

You need to find out what codes are there, post them here, possibly someone on here will have some ideas.

Was this

answer

helpful?

Yes

No

Saturday, January 6th, 2007 AT 5:09 PM

CARUNDELL

MECHANIC
602 POSTS

Bingo. I think this issue is solved. Here's why

1. A disconnected coolant temp sensor will cause the ecm to "see" a default temp of something like 230 F

2. A " cold" engine needs a TON of fuel before it can warm up and go into closed loop. In fact this engine never goes into closed loop because of the disconned
coolant temp sensor. If the ecm is "seeing" a high temp then it will lean out the fuel sent to the injectors, causing a hard start when cold.

3. Though high idle may be caused by a bad coolant sensor, there may be another cause of this.

4. I recommend a new coolant temp sensor and if the high idle persists, then further diagnosis.

Let us know!

Chris

Was this

answer

helpful?

Yes

No

+1

Saturday, January 6th, 2007 AT 9:37 PM