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Long Crank Time when Engine is Warm


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#1 Fitch

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Posted A week ago

My 99 FB jhas always started with just the bump of the key, hot or cold but lately, after the engine is warm, if I stop to get gas or something quick and get back in the car, it cranks longer to start. Sometimes it will fire up, die, and then start. Delphi Fuel pump and filter have about 6K on them but Im still thinking it may be a fuel related issue. I also replaced the FPR a few months ago.

Idle is not as smooth as it once was either. Not a miss but it has some roughness. Runs fine otherwise. Any ideas?

Thanks, Cliff



#2 ZumpTA

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Posted A week ago

Delphi is about as good as it gets in the "reliability" department, so I'd personally be inclined to look elsewhere. If I remember correctly, this condition can be cause by:  Engine overheating, clogged/dirty fuel filter, ignition timing, vacuum leaks or wrong vacuum line routing, bad EGR valve, fowled plug(s), weak battery, a bad spark plug wire or two, and maybe another thing or two I can't think of like overheating ICM. 

 

Where did the EGR valve come from and what brand is it?  Unlike Delphi, just about everything is made in China by the lowest bidder using the lowest quality components on the market supplied by... CHINA!  ...or is a Chinese counterfeit.  Even reputable "Made in USA" brands are moving towards "Chinese Junk" status and can't be taken at face value.

 

There is no guarantee that a brand new component will provide years or even minutes of service, so don't immediately rule out that new EGR valve.

 

 

I'm not sure about the v6, but with the v8 the temperature gauge and the temperature the computer reads come from 2 different sensors.  You could be overheating while the gauge is reading "normal".  Might not be the same with the v6, just thinking out loud here.  An indication of overheating would be "sluggishness",  and I'd suspect you'd have noticed that and would have said something.   ...unless you drive like Grandma that is. 

 

 

Good Luck!


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#3 sea dog

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Posted A week ago

Have you tried doing a fuel pressure check. You would have to consult the 99 service manual available at following link to see what fuel pressure should be. Check when engine is cold & again when engine is hot after turning it off for a while.http://www.mediafire.../?40mfgeoe4ctti

 

Also remove the ignition control module and have it tested by auto parts store. It likes to fail when it is hot.


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#4 Fitch

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Posted A week ago

Delphi is about as good as it gets in the "reliability" department, so I'd personally be inclined to look elsewhere. If I remember correctly, this condition can be cause by:  Engine overheating, clogged/dirty fuel filter, ignition timing, vacuum leaks or wrong vacuum line routing, bad EGR valve, fowled plug(s), weak battery, a bad spark plug wire or two, and maybe another thing or two I can't think of like overheating ICM. 

 

Where did the EGR valve come from and what brand is it?  Unlike Delphi, just about everything is made in China by the lowest bidder using the lowest quality components on the market supplied by... CHINA!  ...or is a Chinese counterfeit.  Even reputable "Made in USA" brands are moving towards "Chinese Junk" status and can't be taken at face value.

 

There is no guarantee that a brand new component will provide years or even minutes of service, so don't immediately rule out that new EGR valve.

 

 

I'm not sure about the v6, but with the v8 the temperature gauge and the temperature the computer reads come from 2 different sensors.  You could be overheating while the gauge is reading "normal".  Might not be the same with the v6, just thinking out loud here.  An indication of overheating would be "sluggishness",  and I'd suspect you'd have noticed that and would have said something.   ...unless you drive like Grandma that is. 

 

 

Good Luck!

 

The EGR is the factory installed one. I replaced the FPR (fuel pump regulator) when I replaced the pump and filter. Guess I need to put a fuel gauge on it.

I try to buy only factory replacement parts when I can. The FPR might be aftermarket. I cant remember. Wires/plugs are fairly new.



#5 Injuneer

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Posted A week ago

Several things than can increase cranking time are:

 

- rapid bleedoff of fuel pressure when the pump primes and shuts off.  Easy to check with a pressure gauge.  You can also try cycling the key back and forth rapidly between “OFF” and “RUN” a few times before turning it to “START”.

 

- a leaking injector (or more than one) flooding the engine. Does the exhaust smell rich when you try and start it?  Try putting the accel pedal on the floor BEFORE turning the key to “START”, and holding it on the floor until the engine starts.  That puts the PCM in “clear flood” mode.  A leaking injector will also cause the engine to idle rougher.  A leaking injector will also cause rapid bleedoff of fuel pressure when the pump shuts down.

 

- faulty coolant temp sensor (the one for the PCM), indicating the engine is colder than it really is.  That causes the PCM to richen the A/F ratio for a cold start, when the engine isn’t cold.  That can also be cleared up by holding the accel pedal on the floor.

 

Unfortunately there is a major problem with poor quality Chinese counterfeit fuel pumps, particularly on eBay.  Where did you buy the pump?

 

FPR = fuel pressure regulator


  • tom99 likes this

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#6 Fitch

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Posted A week ago

Several things than can increase cranking time are:

 

- rapid bleedoff of fuel pressure when the pump primes and shuts off.  Easy to check with a pressure gauge.  You can also try cycling the key back and forth rapidly between “OFF” and “RUN” a few times before turning it to “START”.

 

- a leaking injector (or more than one) flooding the engine. Does the exhaust smell rich when you try and start it?  Try putting the accel pedal on the floor BEFORE turning the key to “START”, and holding it on the floor until the engine starts.  That puts the PCM in “clear flood” mode.  A leaking injector will also cause the engine to idle rougher.  A leaking injector will also cause rapid bleedoff of fuel pressure when the pump shuts down.

 

- faulty coolant temp sensor (the one for the PCM), indicating the engine is colder than it really is.  That causes the PCM to richen the A/F ratio for a cold start, when the engine isn’t cold.  That can also be cleared up by holding the accel pedal on the floor.

 

Unfortunately there is a major problem with poor quality Chinese counterfeit fuel pumps, particularly on eBay.  Where did you buy the pump?

 

FPR = fuel pressure regulator

 

 

 

Great tips! I'll give them a try. I got the fuel pump from Summit Racing. Its a Delphi. I havent smelled any fuel but have noticed a decline in fuel milage. I thought it was winter gas or something. It could very well be an injector. They are original.  Is there an easy way to determine which one is leaking or do you just replace them all? 


Edited by Fitch, A week ago.


#7 tom99

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Posted 9 hours ago

If you pull the fuel rail and injectors as a unit, a little tricky to do because of the cowl, make sure all the metal retainers on the rail that hold the injectors in place are there and then cycle key to on a few times. Drips would be clear. If your going to replace one may as well do them all is how I think as long as money isn’t tight. But get a set of injector seals just in case one rips or gets lost


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