95 k1500 350 tbi stalls

[mtndw]

This problem started about 6 mos ago. It started as a surge on the highway which progressed to cutting out at stop signs/lights.Now it has progressed to cutting out at any speeds usually after the truck has been running for 1/2 hr or more. Wait 5-10 mins & truck starts fine & will be ok for another 1/2 hr or so (not consistant/may not act up anymore) .Changed fuel filter. Checked fuel pressure & it was at 13 psi steady(within specs). Replaced fuel pump anyway as there are 210,000 kilometers on the truck (100k miles or so) & fuel pressure stayed the same. Truck seemed to work ok for a bit but began acting up again. Then replaced the pump relay but I'm back there again .The truck doesn't stay broke long enough to get to find a hard fault. Fuel tank was really clean when pump/sender was removed & all lines were inspected for leaks/damage. Some techs I've spoke with suggest to may try a fuel pressure regulator. Any other direction or troubleshooting suggestions?????

[astralepic]

I've got a 93, 2 wheel, 350 TBI which seems to be heading down the same path. When truck is in park it idles fine. When it's in gear, the idle drops and almost kills the motor before something kicks in, reves a little and prevents the motor from dying. Truck is running as good as it ever has, but I'm at a loss on this one. At first I thought throttle positioning sensor, but truck is fine on the road. My experience with the sensor points to hard shifting which isn't the case. Truck has 230,000 and never had any major mechanical problems.

Any ideas?

[mtndw]

Throttle body gaskets are a common item, as well as the bolts some times require retorquing .Could be a vacuum leak elsewhere as well. When sensors fail or go out of the normal operating range you'll normally get your "check eng lite". Your IAC (idle air control) valve could be getting sticky (on the rh side of your throttle body, just behind the throttle posn sensor). I've heard that they can be taken off & cleaned , but I haven't done one personally. I'm going for a ign module on mine - she works fine when it's working, but die's all together when she quits. Have a read on the chevy C/K forum as there are way more posts on it. Good luck

[2000CAYukon]

Has the EGR ever been replaced?

Try plugging the vacuum line that goes to the EGR valve and take it for a ride. If the stalling goes away, the EGR or solenoid is bad.

//2000CAYukon

[mtndw]

No, not in the 4-5 yrs I've had her & nothing shown in her previous mtce records (he was quite meticulous keeping those). It's something I can try ,but I never heard of this causing a vehicle to just quit at hwy speeds , then just fire back up again (sometimes w/out having to restart, on her own). Those egr's would make her run rough at idle , with loss of pwr & such ,with more consistent stalling all the time ,wouldn't they??? Module may have done the trick, but I want to give it a bit yet before full confidence is restored in her....Knock on wood ....

[2000CAYukon]

Yes a bad EGR will cause a rough idle and hesitations (even at freeway speed). It some cases they can cause stalling.

Since you have already replaced the module, wait to see if the problem comes back and then check the EGR.

//2000CAYukon