HeavyChevy87

Hello Chevy Forum world, new member here with a question that I hope I can find some new answers to. I have a 2001 Chevrolet Suburban LS with the 5.3L that I have replaced the fuel pump twice in, most recently in early 2011. In the few months afterwards, the Suburban ran like a top, amazingly for having close to 250k miles. In the last 6 months, it has been giving me intermittent starting problems. If I drive the Suburban from Lakeland to Tampa, which is roughly a 30-45 minute drive, depending on traffic, I run the risk of the truck not starting again. In this instance, it will turn over and over but never fire off. It seemed to me that it was the fuel pump going in and out, but I am fairly certain that once the pump quits, it quits. If I let the Suburban sit for a long enough period of time, it may start again, but I might also have to give it a boost from some carb and choke cleaner. Bad, I know.

I have seen responses that infer that the Crank Position Sensor could be the cause of the problems, or that it could be something electrical. I know I am not the only one who has experienced this problem, so I am looking for some probable causes and solutions that I can apply.

I appreciate your responses in advance.

oldchevy

If you give it a boost with some gas, does it start right away? Once it starts, does it run good? If so, the check valve is bad in the fuel pump assembly. What brand of fuel pump are you buying? The cheap ones do not last long.

73shark

Welcome to the forum.

Try turn the key on and wait 15 sec and then start. Also check the fuel pressure. And oldchevy is right, replace pump w/ OEM only.

MDTAHOE

More than likely you have a fuel delivery problem, either the regulator or the check valve in the pump (extremely common). Pull the vac line off the regulator before you start it, if there is raw fuel in the line replace the regulator. Cycle the key on for a few seconds off a few seconds making sure you can hear the fuel pump run each time 5 times see if it starts replace the pump. Anything other then a Delphi or AcDelco has almost 100% failure rate. I have heard of many failing in the first week.

HeavyChevy87

The first few times it does fire after carb cleaner is sprayed into the intake, it will start then quickly stutter out. It takes anywhere from 5-10 minutes to get it to stay started. Today I put the pressure gauge on the line and it showed no pressure whatsoever when the key was turned to the on position, but when the key was turned to start it started and maintained pressure at 51 psi. That is the confusing part. The only time the MIL comes on is when the key turned forward to the on position, but once the car is started, it goes away.

As far as the pump goes, I know buying an AC Delco would have been the better option, but at the time funds were tight. In that case, would it be alright to use the existing pump housing but buy a OEM rebuild kit?

Thanks again for your information.

MDTAHOE

Not sure what you mean by an OEM rebuild kit never seen or heard of it. Either way I would not recommend that either. The assembly was redesigned, you need to change the body side fuel pump connector.

Bert1300

I need help. The brake trouble light came on my truck and a short time later the four wheel light came on. No trouble chime until I go through water. Then it will chime 27 or 29 times over and over until it drys out. My 04 Silverado 2500 has 198000 miles and this is the first time to have any trouble. Brakes still work fine. The ABS light has been on for ever but never any problems stopping. Can anyone stir me in the right direction? HELP!

HeavyChevy87

http://www.ebay.com/itm/New-AC-Delco-Fuel-Pump-Module-Repair-Kit-MU170-MU171-MU1088-/170824278591?fits=Year:2001|Make:Chevrolet|Model:S uburban%201500&hash=item27c5eba23f&item=1708242785 91&pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr

This is the module repair kit, do you think this could rectify the issue?

Last night I started the Suburban, drove 6 miles, then shut the car off. I tried to restart it 15 seconds later, but it fired, choked, then shut off. I turned the key forward, listened for the pump, didn't hear anything, sprayed a shot of carb cleaner in the intake and turned the key and it fired up. and ran. It doesn't have a rough idle, but you can tell there is a loping in the engine. Not hard, but if you sit and let it idle, you can feel it slightly.

MDTAHOE

That is up to you I only recommend the entire unit although I have never seen anybody use that before. I do not like doing things twice. You will now be on #3 if you are willing to do it 4 times then go ahead and try using it. Without performing some tests with a fuel pressure tester and a test light there is no guarantee that the fuel pump is the problem.

HeavyChevy87

A few days ago I drove it 12 miles one way to school, steady driving. Shut the car off, went inside for about an hour. Came back out to leave, car wouldn't start. After about 10 minutes, and a shot of cleaner, it started and got a little idle so I jumped in it and got it home as quick as I could. Two days later I went outside to try it, and it would not start. I put the fuel pressure gauge on the schrader valve and had someone turn the key to forward, at which time it said there was no pressure in the line and i did not hear the pump come on. I told the person to turn the key to start, at which time the pressure shot to 59 psi and the car started, then the pressure dropped to 51 psi. I let it idle for 30 secs, had them shut the car off, then turn the key forward and the pressure in the gauge shot to 59 again and dropped to 51 psi. Started up again. Later that night, took it out for a drive. Drove 8 miles, parked, shut the car off, waited 30 seconds, tried to restart it, and it started then stalled out. It so damn confusing to me because if the pump was bad, wouldn't the pump just quit working altogether? I know using an aftermarket brand was a bad choice, but when I had the code checked when it was giving me an MIL and it was p1404. But even the MIL is intermittent. Could it be something in the vacuum or the EGR that could be causing this type of issue?