no hot start - intermittent

[rapidoxidationman]

Been enduring occasional stalling problems for over 6 months now, but have come upon a new hopefully related problem: sometimes the truck won't start up when it's hot. Turns over great, but acts like there's no fuel to burn - no smoke from the tailpipe or anything. Cracking open the bleed valve on top of the fuel filter gives a good fountain of fuel. The IP was changed just before I got the truck with 65K on it, it has over 150K now. I know most of y'all will say the FSD is shot, but I'm kinda wondering about air somehow getting into the system (injectors?) and causing the problem. Thoughts?
Regards,
Rapid

[AndyL]

FSD!

[cudaaa]

I think if it was air it would take longer to screw things up! But if it's only when hot I would think FSD. Try taking a bag of ice and cooling the fsd down after it won't start. If that works you know it's the fsd. Hope this helps. Cudaaa

[MMayhem]

I have a 93 with mechanical IP
yours is electronic . . but

here is a link to my thread for similar problem
http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=006375

I got alot of advice to swap out the IP, but it was not necessary. Just Lift Pump and OPS, and new Fuel Filter.
Runnning strong at 170,000 miles with original IP

[tom.mcinerney]

I do think MMayhem's thread relevant, reminds of tbogemirep's experience with a clogged filter. MorePower has said the fuel out West needs lubricity additives most; Damork was advised that fine abrasives in fuel wear fuel solenoid, cause to stick.
Apparently the liftpump is working at least some of the time. I think on '96/up trucks the PCM orders the LP relay to energize the LP when glowing, cranking or running. IF the relay contacts are burnt the connection won't be consistent. You could replumb the fuel sys; but maybe adequate to check for airbubbles with a transparent hose section at input to FIP, much easier.
The alternator output could be dropping off when hot, voltmeter should give clue. I would see to it that the engine harness ground(s) in area of rear passenger head are removed, cleaned, and reattached smothered in syn grease to a stud/bolt that had been removed/cleaned/retorqued. No harm checking batt cabling/grounds.
FSD bolts/mtg nuts snug?
Radiator, cooling sys clean& cool?
The Fuel, Engine Cooling, and Electrical systems may(or not) need maintenance; all have to function adequately for the thing to work well.

[rapidoxidationman]

more info:
I replaced the fuel pump about 3 months ago after the original started to sound intermittent.
I use 8oz of powerservice (grey bottle) religiously with every fill up; the boys at NAPA advised me on the "dry" fuel we have out here.
The fuel filter is not old; less than 4 months (12K miles)
Seems like when the truck WON'T start is after driving in the rain (and when the moon is in the seventh house and jupiter aligns with mars...)
Voltmeter is telling me good volts on running and not bad on starting - just above the red zone and the engine turns like crazy.
The truck started 45 minutes after I started this thread.
I'm thinking of pulling the intake manifold off this weekend and checking the fuel shutoff solenoid wires for corrosion... Thoughts on this?
Thanks,
Rapid

[FarmerDale]

My .02 says that there could be an electrical connection problem. Personal experience had a poor ground from FSD and a couple loose pins in the FSD connector. Both problems, plus a new OPS and lift pump (originals), got my rig moving again.

The assumption I have is that the extra power drain upon starting leaves little extra to jump any gaps at those points, and the senstitive electrical components don't work, meaning in this case, fuel doesn't get through the IP.

[tom.mcinerney]

Rapid--
I think it's eng wire hrnss psgr rear head stud loose. This is PCM+LP+FSD+....
Then again, the ignition switch also effects lots, but they seem to last longer in vehicles after '95.

If only pull top section of In Man off i believe can access most connections at FIP. But if pull off entire In Man, then can do FSD transistor mtg nuts, and also FSD mtg bolts(they're also oft reported loose). But should really have a new Heat Transfer Pad to re-install FSD; if not maybe reuse (if no tear) with a little dielectric grease smear....Again, if remove entire In Man, can look over the fuel hoses to filter assy, and FIP.

If wouldn't hurt to retorque all In Man mtg bolt/studs; and clean up the one(s) with grounds!

When troubleshooting/maintaining digital electronics, one of the best proceedures is to carefully unplug, {inspect/clean/coat}, then reseat all the wiring connectors. Many of us have found that after many miles the connectors are 'good as new'.

Inspect all wires around pump for abrasion, etc.
The F-shutoff solenoid is not mysterious in that it makes a "click" which is audible and can be felt by hand, when cycle ignition on/off.

The voltmeter has indicated many system voltage problems caused by deranged alternators. I don't recall anyone being alerted to low circuit voltage [like at FSD or LP] by the instrument panel voltmeter, though.

[ucdavis]

very high probability it is electric.
A) you didn't say if it had codes?
B) I'd try the following:
1) check air in IP by replacing black fuel return tube that exits front of IP w/clear tubing. You'll see any air. Some bubbles are normal. Big bubble after it sits for a while is too.
2) replace OPS if it is not fairly new. Its easy to do & only about $25 at your local NAPA or AZone.
3) THEN, I'd remove the IMan. If you can get to the wire connections on the FS w/just the upper manifold off, you have my eternal respect.
4) could be the Fuel Shutoff Solenoid sticking when hot or getting weak (since you have some stalling too). These can be user-replaced w/great hygenic care (clean well around the base B4 removal); get new part from Stanadyne or off a spare IP)

If you get to #3, AIWY, I'd do a remote mount of the FSD (after torquing the nuts). A cooler like mine works fine w/heat transfer paste from Radio Shack; got the alum sheet from local metal/welding outfit. Since you have no warranty left on IP, just splice needed length of wire into the FSD harness.

I'd bet a buck AndyL is right.

[panhead9]

I just had this problem on my blazer Had no error codes but would not start when hot intermitently or stall for no reason I found after pushing on plug on FSD all worked after that. removed plug and used some dielectic on it all seems well now. What a bitch getting to that plug with manifold on!