Hard Starting ( fuel pump )

daevans315 · Post by **daevans315** » Wed Sep 13, 2006 5:47 pm

The crew has been taking longer to start over the last few months. 3 or 4 months ago I noticed that maybe 1 out of 10 times I went to start it it would take 3 to 5 seconds of cranking to get it started. It has gotten gradually worse so that now it is the norm to take that much cranking to get it going. Waiting 5 seconds with the key in 'run' for the fuel pump to turn off makes no difference. Hot or cold seems to make no difference. Many of my 'googles' point to the fuel pump but none of the other symtoms are there (good fuel pressure, hp, and pressure stays up with key off). I'm about a year from my last tune up... No pending codes in the computer.

Any ideas?

Post by **HenryJ** » Wed Sep 13, 2006 5:52 pm

When was the last fuel filter and injector cleaner?

How old is the battery?

Inspecting the ignition components should be the first thing on your list now.

rick · Post by **rick** » Wed Sep 13, 2006 7:41 pm

Just got my truck back from the dealership 1 1/2 weeks ago for doing the same thing. It has 58000 miles on it. Turned out it was the fuel pump. Was putting out 45lbs of pressure instead of the required 50lbs. Was under an extended warranty with a $50. deductable. Otherwise it would have been $800. at the dealership. I had them also fix a rear window switch that was bad also.
On the lighterside, my wifes 2000 Blazer had a bad fuel pump, the pump was $150. at the autoparts store and I changed it myself. The average estimate I was recieving was $600. to $800. at the shops.
I was told one time that if you always run you gas below a half a take of gas it slowly wears out the pump because it is working harder and hotter wearing out the pump. Above a half tank the gas keeps the pump cool and not working as hard.

daevans315 · Post by **daevans315** » Fri Sep 15, 2006 5:53 am

HenryJ wrote:When was the last fuel filter and injector cleaner?

How old is the battery?

Inspecting the ignition components should be the first thing on your list now.

Fuel filter was done April of this year.
I'm running a take of sea foam right now to see if that helps.
Battery is a year old.

Plugs are about 30,000 miles.. I can't remember what I put in now but I would guess I would be registering a miss fire if they were bad enough to cause hard starting.

I pulled the distributer cap off a few thousand miles ago and it all looked like new.

I swapped the fuel pump relay with one of the other relays under the hood(fog lights?? don't remember) to see if it was acting up. No change.

Has anyone looked into the ignition switch, crank shaft sensor, oil pressure, fuel pump enable interlock... I know on my 97 (having had to trouble shoot it extensively) that there are 2 separate, independent paths to turn on the fuel pump. One with the ignition switch and the fuel pump relay, the other one is if the computer sees oil pressure and the the crank shaft position sensor registering RPM's, it will enable the fuel pump through a different path. (attempt a a fail safe I think)
Did they keep this on the newer S-10's?

daevans315 · Post by **daevans315** » Fri Sep 15, 2006 5:57 am

rick wrote:Just got my truck back from the dealership 1 1/2 weeks ago for doing the same thing......

I hope its not the fuel pump just because of cost. I'm questioning the accuracy of my fuel pressure gauge now. Its an autozone special and I wonder if its off a little. I was getting right at 50 - 52 psi. It wouldn't take much for that gauge to be off 3-5 PSI. I'll see if I can dig up friend with a gauge to compare.

killian96ss · Post by **killian96ss** » Fri Sep 15, 2006 9:02 am

I'm still having the same problem, and I'm 90% sure it is the fuel pump. I still need to take it to the dealership if I can find some time, but keep us posted on what they find to be the problem since my CC is doing the same exact thing.

Here is the topic I started about this problem. Stock Fuel Pressure Question

Steve

daevans315 · Post by **daevans315** » Fri Oct 06, 2006 11:58 am

Well I ran a tank with sea foam through it and things got a little better. It went to hard starting about half the time. I ran a 'normal' tank through it and then another can of sea foam on the next fill up. Now we are back to rarely hard starting. (1 in 10 or less). I'm going to let it go for a while and see what happens. I'm guessing whats going to happen is I'll be changing the fuel pump 10 below zero in Jan instead of this fall. But that could just be my pessimism talking.....

daevans315 · Post by **daevans315** » Mon Oct 23, 2006 12:06 pm

I got to put a gauge on mine when it was actually acting up. When you turn the key it goes from 0 PSI to 60 ish while the pump is running. In less than 2 seconds after the pump stops, back to 0. This just about has to be the foot valve on the pump as if it was in injector im guessing after 5 or 6 times of doing this it would be very flooded. It is not.

So, does anybody have the GM part number for the pump or any experience with any of the after markets? My GM guy says he needs the VIN to tell for sure what pump it is and GM-PartsDirect.com doesn't list one at all for the 2002.

I'm very likely to go back to GM as this doesn't look like a real fun job and I don't want to do it again.

Post by **HenryJ** » Mon Oct 23, 2006 3:12 pm

I am pretty sure you have to buy the module, This is the pump , sender, etc. all in one assembly.
Last 8 of the VIN is the best way to be sure when ordering from your dealer.

daevans315 · Post by **daevans315** » Fri Nov 03, 2006 2:33 pm

I just got my fuel pump in from gmpartsdirect.com. I was assuming that this was a 'drop the tank' job. However, the directions that came with the pump specifically state to remove the bedliner and then remove the FUEL PUMP ACCESS PLATE!!!!. Do we actually have one? Please tell me somebody has had their bed liner out and seen this!

killian96ss · Post by **killian96ss** » Fri Nov 03, 2006 2:43 pm

daevans315 wrote:the directions that came with the pump specifically state to remove the bedliner and then remove the FUEL PUMP ACCESS PLATE!!!!. Do we actually have one? Please tell me somebody has had their bed liner out and seen this!

FUEL PUMP ACCESS PLATE????????????????????????????

This is a joke right?????????????????????????????

Steve

daevans315 · Post by **daevans315** » Fri Nov 03, 2006 2:48 pm

killian96ss wrote: FUEL PUMP ACCESS PLATE????????????????????????????

This is a joke right?????????????????????????????

Steve

I'll take that as a no.....

I bet the directions are for the blazer... now that I read on.. I says to remove the jack, spare tire cover and spare.

F9K9 · Post by **F9K9** » Fri Nov 03, 2006 2:55 pm

You have to drop the tank to get at it. If we had regular PUs you could just raise the bed to access it but, the pump/sending unit is under the cab on CC.

killian96ss · Post by **killian96ss** » Fri Nov 03, 2006 3:08 pm

daevans315 wrote:
killian96ss wrote: FUEL PUMP ACCESS PLATE????????????????????????????

This is a joke right?????????????????????????????

Steve
I'll take that as a no.....

Hopefully I did not offend you with my reply.

If so I am sorry since that was not my intention.

I wasn't sure if it was a joke or if GM just forgot to install a FUEL PUMP ACCESS PLATE on my CC.

Steve

daevans315 · Post by **daevans315** » Fri Nov 03, 2006 5:11 pm

killian96ss wrote: Hopefully I did not offend you with my reply. If so I am sorry since that was not my intention. I wasn't sure if it was a joke or if GM just forgot to install a FUEL PUMP ACCESS PLATE on my CC.

Steve

Don't worry.. it takes much more than that to offend me....

You didn't insult my truck or my lady so its all good.

JaVeRo · Post by **JaVeRo** » Sun Nov 05, 2006 9:13 pm

When you get the tank off there will be three lines. The middle line is the vent that goes to some kind of smog doodad that I can't think of the name for right now. Look closely at that line where it makes a bend near the cab. Mine was rubbing against the cab and was about to wear thru. It kinda looks like the line was designed for the extended cab and the crew cab got in the way.

James

daevans315 · Post by **daevans315** » Wed Nov 08, 2006 8:12 am

I put the fuel pump in last night. About a 3 hour 2 person job. I pulled the drive shaft to give some more room to work. I highly recommend that. I also used a transmission jack to lower and raise the tank. That was a HUGE help. Finally, I could have done most of the work by myself but getting the lock ring that holds the fuel pump assembly back on was, at least on mine, a 2 person job. One to hold the fuel pump down and compress the springs and new O ring and one to work the lock ring back on.

But its all fixed. Starts like it should and fuel pressure stays above 50 for 5 mins after key is off.