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1999 Suburban Fuel Problem

Hello,

My 1999 GMC Suburban C1500 2WD began starting hard and running rough a month or so ago. The problem got to the point that I would have to crank the engine repeatedly to start. The dealer diagnosed a faulty fuel pump and has replaced the fuel module ($650+diagnosis!). They called today, when I was expecting to pick the truck up and they said "we have bad news. The truck started up perfectly after putting in the new pump, but when we turned it off, it won't start again." He said that when he tries to start it, it runs for about a second and then shuts off. He says it is my "built in" security system that is causing the fuel pump to shut off after one second. They want to replace the ignition cylinder and several other parts in the steering column and see if that helps. They have already recommended that they replace the rotors/drums pads/shoes all around (for $1650). I declined on the brake job and was hoping to get my truck back today, now this. To me it sounds like the the fuel pump installation is just not working well--not that some hidden security system suddenly requires all this work.

Thanks for any advise!

Eric K.

Reply to
eric_k
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Eric, it is a common malfunction in 98 and 99 chevy vehicles across the spectrum. There is a little electronic box called a "body module". When it takes a shit(ironically about the time the lock cylinders in the ignition do too), your "theft-deterrant" system kicks in and acts just like the dealer says.

BTW, I put theft-deterrant in "" because even if you don't have the factory installed alarm, it will still do the same thing. My mom's 98 Malibu is on it's second body module and it's beginning to fail after 2 years.

Sam

Reply to
GaWd

If the asshole mechanic had just run a fuel pressure test before throwing a pump at it you'd be $650 richer right now. I'd raise holy hell.

Doc

Reply to
"Doc"

Well, I went down there yesterday afternoon and asked if I could see the car. I watched them pull up a B1626 code on their scanner. I turned the key forward and the security light came on steady. So I went ahead and the thing started right up. I asked if they had checked the fuel pressure before replacing the pump and they said they hadn't...but that since my fuel gauge was bad (which it was) they thought the bad fuel level sending unit was causing the problem. So I guess I paid $650 for the convenience of not using my trip odometer for a fuel gauge. Anyway, suffice it to say that I turned down their offer to charge me $700 to fix the PassLock system.

I've poked around and found several PassLock 2 bypass kits for use with after-market add-ons/security systems. PeripheralElectronics.com has two that cost between $30-$40. What do you think about me getting one of these and just bypassing the whole (faulty) system? Although I can usually get it started, my wife has run the battery down trying. She doesn't want to get stranded somewhere--so I do need to fix the problem.

Eric K.

Reply to
eric_k

Eric-

Let me know if that bypass works. I get tired of having my mother stranded when her body module decides to act up.

Sam

Reply to
GaWd

Actually, strike that. I spoke to them on the phone and they say that removal of the body module(which is causing your starting problems), is impossible unless you convert to carburetion.

Sam

Reply to
GaWd

I can probably talk you through using a bypass module on either the malibu or the pickup... it does not bypass the bcm itself, it merely bypasses the ignition cylinder itself.I change the bcm itself 1 out of every 10 cars/trucks with this problem. Most likely it's the ignition cylinder(passlock housing) or an issue with the wiring.. There is a bulletin for wiring issues on the c/k trucks and blazers for soldering the passlock wiring.. If you have a remote start I would check and rewire that first.. A lot of places twist and tape, not solder or crimp.. When these fail you will have a start, then stall... it will fire up and run for approx 1-2 seconds, then die... you will then have a flashing security light for 10 minutes... the truck will not start for 10 minutes.It will keep on starting and stalling, even if the fault is repaired.. you will have to leave the ignition on for 10 minutes to reset the system and try again... If this is what was happening before the fuel pump, then yes, they messed up... how many miles are on the truck?? I know I will get flamed, but 100k with a original pump is pretty good.. I have seen a few 200k pumps out there, but I have done a lot of pumps at around 100k...

Reply to
bobo

Thanks all for the input and research. I'm going to try the bypass module. It's cheap enough that I'd rather try that and see if it works. I don't have a remote start or any other related after-market stuff on the vehicle. Had just over 70K when this all started. As far as the bypass goes, I'm looking at Peripheral Electronics' PLGMD or PLGML (learnable) units.

Eric

Reply to
eric_k

Reply to
bobo

I hate to point this out, AGAIN, but if you do indeed have a failing body module-which will exhibit the exact symptoms you have-this bypass won't do crap for you. I've already called the company and asked about it. They told me that the bypass module doesn't eliminate the body module.

So if yours is acting wonky, it'll still act the same way with the bypass module. Zero sum game.

Sam

Reply to
GaWd

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