wtf

[denn54]

2001 explorer 4.0 wont start when cold, fuel filter changed,thermostat housing unit, o-rings all changed. Starts with starting fulid and keeps running. Anybody having the same problem ?

 

[Flash]

I don't know this from personal experience_

The spring loaded brushes in the fuel pump can contract causing intermittent or no contact causing the fuel pump to fail in very cold weather.

 

[my98nnj]

Starts with starting fluid and continues to run on its own?
Check the engine coolant temp sensor, make sure it's within spec cold.

 

[SoNic67]

I would say fuel pump.
Put the key on contact and listen for the fuel pump noise (should run a few seconds to build up pressure before start). If you don't hear it, try hitting the side of the tank to see if it starts.

 

[koda2000]

I would say fuel pump.
Put the key on contact and listen for the fuel pump noise (should run a few seconds to build up pressure before start). If you don't hear it, try hitting the side of the tank to see if it starts.

The OP says it stays running once he starts it on starter fluid, so that doesn't sound like the pump isn't running. It might have low pressure though. He should check the fuel pressure at the fuel rail (s/b around 65 psi on an '01). The coolant temp sensor is also a possibility.

 

[pcam13]

dont use ether too much... It will stick rings and damage other internal components and or ether lock. I work on diesels for my job. Very dry stuff...

 

[bill06447]

By cold start, you mean every time the truck has been sitting? Or won't start when temps are below x degrees?

Bill

 

[SoNic67]

The OP says it stays running once he starts it on starter fluid, so that doesn't sound like the pump isn't running. It might have low pressure though. He should check the fuel pressure at the fuel rail (s/b around 65 psi on an '01).

Exactly. Also, once the truck starts vibrating, it might let the pump start running - that's why I suggested the tapping test. Kind of like hitting the starter motor to help it start...

 

[koda2000]

Exactly. Also, once the truck starts vibrating, it might let the pump start running - that's why I suggested the tapping test. Kind of like hitting the starter motor to help it start...

Yes, I'm familiar with the "tank thumping" procedure. Easy enough to try I guess.

 

[denn54]

fuel pressure test was 40 psi

 

[denn54]

By cold start, you mean every time the truck has been sitting? Or won't start when temps are below x degrees?

Bill

If temp outside is below 20 it wont start, just crank. Can start with starter fluid. Had fuel pressure test, 40 psi .

 

[denn54]

Starts with starting fluid and continues to run on its own?
Check the engine coolant temp sensor, make sure it's within spec cold.

Had thermostat housing unit replaced so it has brand new eng coolant temp sensor in it.

 

[bill06447]

Check the two temperature sensors that feed the PCM, both coolant and air. I don't believe it is the same one that feeds the gage. It sounds like one or both is faulty. A $100 scan tool from China Freight is indispensable in these cases, and is perfectly adequate for the person who only services their own and friends fleets.

Bill

 

[denn54]

Check the two temperature sensors that feed the PCM, both coolant and air. I don't believe it is the same one that feeds the gage. It sounds like one or both is faulty. A $100 scan tool from China Freight is indispensable in these cases, and is perfectly adequate for the person who only services their own and friends fleets.

Bill

Thanks Bill, will let you know.

 

[koda2000]

fuel pressure test was 40 psi

40 psi is a bit on the low side. On your model (2001) it should be 65-67 psi. When's the last time your fuel filter was changed? (Never mind, I see you say it was changed recently).

Note: Some fuel pressure testers don't compress the Shrader valve enough to get a good pressure reading. You might try removing the valve during the test.

 

[travis8352]

2001 explorer 4.0 wont start when cold, fuel filter changed,thermostat housing unit, o-rings all changed. Starts with starting fulid and keeps running. Anybody having the same problem ?

similar problem except i havnt replaced anything. only put heet in the tank. mine wont start at anything below -5 and tuggles below 0. its -10 so im fairly certian it wont start today. thought it was possibly the fuel pump cause all mine does is turn over but mine seems like when its really cold its not getting spark.

 

[bill06447]

similar problem except i havnt replaced anything. only put heet in the tank. mine wont start at anything below -5 and tuggles below 0. its -10 so im fairly certian it wont start today. thought it was possibly the fuel pump cause all mine does is turn over but mine seems like when its really cold its not getting spark.

According to that mythical piece of writing in the glove box, its recommended to give it 1/3 throttle while cranking in extreme cold.

Bill