1992 g20 van fuel issue ?

[fear1209]

ive got a 1992 chevy g20 conversion van it has roughly 166k on it
engine is the 5.7

i started up the van and it ran / drove fine for a about a 2 mile run on the freeway, as i got off the freeway it started acting up i gave it gas and there was a flat spot with no response had to hold it about half way down.

anyways i got to where i was going and put the van in park then it just died / stalled out.
i turned it over it fired right up put it in gear was fine however as soon as i touched the gas pedal it died again. this time simply turning it over would not start it.

i held the gas pedal to the floor and after about 10 sec's of cranking it started again nice big puff of black smoke from the tailpipe aswell as a strong odor of gas. put it in drive again it died now it only starts if i hold it to the floor and it lets out a nice puff of black smoke everytime.
it will not idle unless i rev it up really high for a min or so then it will sometimes idle on its own.

but stalls once its in gear or you touch the gas pedal. feathering the gas pedal has no affect on it at all to prevent it from dieing.
there was no check engine light on and there are no codes stored any ideas would be great.

also on a side note not sure if it could be related if i turn my left blinker on my speedometer needle starts to bounce up and down intill blinker is canceled. and if you turn the headlights on the speedometer stops working altogether.

thanks in advance.

[MT-2500]

Did the blinker and dash problem start at the same time as not running right?
I would go over battery and battery cables and power and ground feeds.
Also check ign switch and wiring for working good.
Is battery good and at full charge and alternator charging good?
Has any repair work been done on it right before it all started?

[fear1209]

only recent work ive done was a simple oil change u joints and rear wheel bearings. and this morning i have replaced both postive and negative battery cables as they where in bad shape aswell as replaced the engine ground strap. made no difference i still have the same issue van will start if i hold it to the floor gives a nice puff of black smoke will stay running at wide open thortle however strugles to do so.

im wondering if it could be a faulty fuel pump ?
or if its just flooding out somehow.

the speedometer issue has been going on for about a month now.
and once in a while if i reved up the motor a little bit it would sort of stumble and want to die as it got back down to idle speed. that issue
was intermitant prior to now.

swapping out battery now with a brand new one and i have a spare alt ill put in to double check that aswell.

[fear1209]

changed the alt and put new battery in still the same.

[MT-2500]

A fuel pressure Gage will test fuel pump.
Throttle body injection fuel pressure specs are 9-13 lbs pressure.
Also check fuel filter.

Check for good hot blue spark to all plugs.
In them years the dist module and PCM gave a lot of problems.
The computer can sometimes be tested with the old tap/twist test.
Also check EGR valve for sticking open.
What is engine vacuum reading at idle and at 2K rpm?

[fear1209]

ok so it decided to start and kinda run fine however i now get as service engine light, come up with the following codes.

code 15 Coolant Temperature Sensor (Low Temp Indicated)
code 34 Manifold Absolute Pressure Sensor Circuit (Low Sig)


any ideas as to what would trigger these.

also have a slight grey/whitish smoke out the tail pipe well running and if i rev it up a bit alot of black carbon looking build up comes out.

note i couldnt check the vacum as i cant find my vacum gauge.
ill pick one up in the morning.

[MT-2500]

Yes a bad/low engine to pcm coolant sensor signal to computer will set codes 15.
Check coolant sensor and wiring to PCM.

Code 34 is a bad/low map sensor signal to pcm.
Check map sensor and engine vacuum to it and wiring to pcm.

Also make sure sensors are pluged in good.

If no problem with sensors or wiring or engine vacuum check the PCM coolant and map sensor readings with a engine scanner.

Low coolant and map sensor reading to pcm can cause engine to run rich and flood and black smoke out tail pipe.