GMC Repair: Engine bogging when cold, auto zone auto parts, auto zone auto parts store

Question
Hello there! I own a 1993 GMC V8 full size conversion van and the engine bogs down when it is cold. In the morning when it is cold I will start the van and take off. I give it gas and the engine seems to cut out, but when I take my foot off the pedal it comes back to life. I can only drive it at speeds of about 20-35 MPH until it warms up after about 10 mins.  In order to drive it I need to just touch the pedal a little bit and the van moves, but if i give it more gas, it will not accelerate, the van slows down until I lift my foot a little or take my foot off completely. When the engine warms up, I can drive at speeds of 55 or so, but if I put the pedal to the floor it bogs down even when warmed up, and it will slow from 55 to 25 on a hill or incline. I checked the throttle body and there seems to be sufficent gas entering from both injectors in a nice spray. I replaced the cap and rotor. The contacts on the cap were coroded with some flaky white stuff. The plugs are the 4 pronged platinum bosch plugs. It also sucks gas like a pig and smells as if it was running rich.the check engine light is not on. The transmission has just been re-built. I was thinking a fuel problem but that would not explain why it runs better when it warms up. I went to a local  "Auto zone" auto parts store and they suggested the MAP sensor, so I removed it and brought it in for them to test and it tested fine.  I am pulling my hair out!! I would very much appreciate any information!!! Thank you so much!!

Answer
The FIRST thig to check is the color of the electrodes on the base of the spark plugs to see if they are burning correctly.

SECOND would be to perform a fuel pump PRESSURE and VOLUME test on the pump. It is very possible that you have a worn fuel pump that when cold runs much slower than it should thus causing a loss of pressure or volume to the injectors. This is NOT uncommon.

THIRD would be a manual test of the TPS (Throttle Positioning Sensor as if it has an intermittent afult it will NOT illuminate the check engine light on the dash.

Fourth would be to make sure that the EGR is not being fully opened by a faulty intermittent EGR CONTROLLER of which also may or may NOT illuminate the dash light.

What mechanical work or ANY kind of work has been performed on the vehicle recently ?. As most problems that occur after a recent repair was made can be traced back to the area of where the repair was made as a vacuum line may have been knocked loose or a wire connection came loose, Look around in the area where work was performed.

Could it be possible that you got a load of water during your last tank of gas ?. try installing 2 cans of DRY GAS or similar product and see if your problem starts to slowly clear up.

autohelp