Engine Bog, No acceleration~ My Fix

[Taheezy]

I came to this forum for help and it gave me some ideas....

~1996 Tahoe

Recently had a problem with the Tahoe loosing power on Acceleration. Started after an 850 mile trip, but at home (Luckily!) The next day after the trip, the truck would not accelerate like it normally does.The engine would Bog down on wide open throttle, backfire thru the intake/filter and then sometimes eventually shut off. I changed the MAF sensor, no fix. I listened to the fuel pump to see if it pressures up...and it does. for like 3-4 seconds it runs when I turn on the key....then stops. Wait about 15-20 and do the same thing it runs again and stops.. Does that mean it bleeds down too quick?
So I then poured Seafoam down into the intake/throttle body butterfly and let it set for 10 minutes. Cranked the truck up and it gave it some throttle...yeah it sputtered for a few but then after about 20 seconds it had power like normal..I was amazed and in disbelief as this sort of thing does not happen to me. If its a million dollar problem then that's what it usually turns out to be with my luck. Well from that point on, I decided to use the rest of the can. Pour about 5 oz's in a jar and sucked it in to the intake. It smoked like H3LL but after the smoke cleared my truck ran Normally. Put the rest of the Seafoam in the tank and road tested it. Power was back to normal. What the hell could have been cleaned in there that was causing it to bog down since I have never seen the inside of this spider thing I keep reading about? I had already been to my local "Cash for Clunker" Gold mine and scored an MAF, TPS, Fuel pump... for 20 bucks and was ready to jump in. That Fuel Pump is a B*Tch to change so I decided to save it for last...which the problem cleared before I needed to change it. Where is the Fuel Pump relay located? Wanted to check the Fuel pressure but the only place I can see where that is possible is the where the fuel line screws into the fuel filter. Or have some sort of adapter to attach to that connector on the spider. Does anyone have a photo of such adapter or know where one can be had?

Thanks
M0on

[LT1Silverhawk]

Seafoam really does clean the hell out of a fuel system. I've been using it for as few years on several cars and it has never let me down.

One word of caution is that Seafoam should not be used through the intake too often as it will cause things to break.

In your case, have you checked the air and fuel filter? I've noticed a drop in power and fuel economy right after a long trip and those two are usually the culprits for me.

[old_master]

Fuel pressure test port is at the rear of the engine near the distributor. Key on, engine off, fuel pump running, pressure must be 60psi to 66psi and must remain above 55psi for 3 to 5 minutes after the fuel pump shuts off.

[777stickman]

In answer to your ? about the fuel pump. With the key on engine off it will only run for 2-3 seconds. This is normal. Pump will only run continuously when the VCM sees ignition pulses (cranking or running). Pump relay should be in the under hood fuse/relay center.