Engine/Transmission (1998.5 - 2002) Occasional hard start

[AggieJustin]

I've got a buddy with a '99 that has a occasional hard start condition, and it is very occasional. Instead of starting up after a couple of revs, he'll have to crank for 4-5 seconds to get it started. I've checked the fuel pressure, and the lift pump is fine. But whenever I've checked, I haven't been able to replicate the hard start.



So what might be causing this problem? I was thinking possibly the check valve on the fuel return line. Either sticking close and causing too much fuel pressure at the inlet, or sticking open and draining fuel outta the line between the filter and the pump. Does anyone have part number, or a price on the check valve?



Anything else I should be looking at??



Thanks,



Justin

 

[Sticks]

Fuel pressure?



Is his LP healthy?

 

[Steve Campbell]

You might try....

re-tightening all of the ground straps (including the ones on the battery terminals) that you can find under the hood and dash. I have solved some really "interesting" problems this way.



Your on the right track by having..... already..... checked the lift pump pressure. The "check valve" in the return banjo has a very small hole in it and does bypass some fuel all of the time. I think if it were sticking open , you would have poor lift pump pressures... . JMO. Sticking closed is another matter. You might try unplugging the wiring to the lift pump and cleaning it out real good... ... adding some "dielectric" grease and plugging it back together. Maybe it has some corrosion/water in there.



Then again... . maybe this is the beginning of the end for his lift pump. Can you fix him up with a "temporary" fuel pressure gauge (He really needs a permanent one) to see what is happening in the real world with his pressures. He just might find out that on that ime when he goes to start and has to crank that his pressure is gone. These lift pumps usually give some kind of "warning" period when they fail if you are monitoring pressure.



Hope that helps.

 

[Sticks]

Re: You might try....

Originally posted by Steve Campbell



Your on the right track by having..... already..... checked the lift pump pressure.

Oops, and I read the first post three times. I should know better than to post before I have my coffee.

 

[rashwor]

Drove my '99 like that...

for 2 years with it slowly getting worse. New VP44 installed in May 2003 solved the problem. I hope this is not his problem. Hook up a scan tool and see if any codes are set. The key on-off-on-off-on will not display any codes in the odometer window on '99s.

 

[AggieJustin]

Thanks guys. The last time I checked, the fuel pressures were good. He just had the lift pump and the VP44 replaced at the end of last year. Since that time we've been checking the LP pressure periodically to make sure it doesn't go out again.



This hard start has happened on my truck once. When I tried starting, I glanced down at my FP gauge and it was pegged over 16 psi. I shut the key off and waiting for the pump to stop running, then tried starting and it worked fine.



I've been telling him to get a permanent gauge, looks like I'll need to work a little harder on him now.



I'll have to get a scan tool and check for any codes. Just haven't had the time yet.



I'll also look at all the ground straps, never rule out a bad ground.



If anyone else has any other ideas, feel free.



Thanks,



Justin