89 Burban TBI 350 Running rough, stalling

[swearingsailor6]

Hey guys, I am new to this forum, and would like to say HI! Im from Mitchell, South dakota, and have had square bodies since I was 13...never without one!

anyways, My current rig, an 89 GMC Suburban 4x4 w/ TBI 350, 1500.

I was cruizing the other day, stopped at a stop light, and when I went to take off, it died on me. Started back up, and coughed and bucked all the way home.

As of right now, I have replaced the plugs, wires, cap and rotor, pcv valve and gromets, IAC and the MAS. The only way it will run now, is if I have the MAS vac line unhooked, otherwise it starts but quits right away. Even with feathering the gas, it won't run. But even with that line unhooked, it runs just enough to put it in gear, then dies.

I checked all the vacuum lines and replaced 2 that looked like they could be bad, but everything else looks good. I don't have a pressure gage to check the fuel pressure...but thinking of taking it in to a mechanic and paying them to fix it. It is a big headache, and with my line of work, I am on call 24/7 and work too much to fiddle with this too much.

Anyone have any ideas? I hate throwing parts at it with no results...it really sucks!
See you on the road!
Ryan

 

[82chevy350]

This is kinda like my problem

 

[bucket]

Hmm, Mitchell SD. I'm pretty sure that's where I bought a Camaro back in '02. Nice place.

Engine light on? It does sound like it could be fuel pressure, have you replaced the fuel filter?

Ah, I even remember the guy's name I got the Camaro from. Luke Cosgrove... know him?

 

[Manbearpig]

Check the fuel pressure.
Totally sounds like your fuel pump is dying.

 

[crazy4offroad]

Almost sounds like TPS to me. Really need a manual and ohm meter to check sensors and be sure of what's wrong before replacing it.

Is your name Mitchell or Ryan?

 

[swearingsailor6]

My name is Ryan...I have everything I need, at my garage that is 150 miles away....We just moved to Mitchell, and I have no place to store all my toys and tools here. I also have Chiltons and Haynes there too...doesn't help me at all when I can't read them!

This is just a temporary living situation while we are house-hunting, but hopefully soon we will be buying a house.

I will be looking into the fuel pressure...I have a couple guys at work that are gear-heads, maybe one of them has a gage that I can use. I have a fluke at work that I will be borrowing....Already had to borrow the company truck! lol
Thanks guys...I will keep you informed on what I find.

 

[swearingsailor6]

Oh yea, the Check Engine Soon light is on, had it scanned by oRiley's, and came back with MAP/MAS Too low/too high, And a bunch of other codes....the guy didn't know what to make of so many coes at once....

 

[swearingsailor6]

Anyone pull the tank on an 89 burb before?? I see the 2 straps...whats the mess of wires on top look like?? Any helpful hints be great before I dive into it.....
Thanks!
Ryan

 

[crossy's son]

Replace the Coolant Temp. Sensor right away. The $8 one on the front of the motor next to water neck.

Unhook it first and see if it runs better. This is most likely the problem due to the symptoms you're describing.

 

[swearingsailor6]

I will give it a shot, its cheap! Can't hurt anything anyways.