please help

1994 Roadmaster wont start changed fuel pump and fuel pressure regulator still only starts and dies . Please help this is my only way to and from work.

Forgot to add car ran good all day yesterday . Tried to go to store around 6 in afternoon and it wouldnt start
Droped full fuel tank and replaced fuel pump yesterday . Car still would not start . Bought and installed fuel pressure regulator today same thing .

When you turn on the key but don't start the engine, can you hear the fuel pump whirr?

yes you can

Start from the beginning. Why did you change the pump? How long does the engine run for before it dies, 1 second, 1minute? More back round info would help. Check your grounds as well, especially the grounds that bolt to the cylinder head with the coil/ignition module bracket.

Mike

Dont be offended but what about the fuel filter?Do you smell raw fuel or see any puddles under
the car?
Jim G

it starts then dies . changed fuel pump becuse it will run on carb cleaner as long as you keep hitting it . ran perfect up until 6 pm last night . havent cked groungs as of yet . seems to crank and fire just no fuel

no puddles under car cant smell raw fuel . not offended just looking for any help i can get . thank you everyone for ideas and replys .

fuel filter would be a logical thing to change, and cheap

also have you checked the applicable fuses and relays?? I guess if the pumps running I doubt it would be that

Pass lock shuts fuel off, any pass Lock light on the dash? Check those grounds yet? Has the car been running good up to this point? How does it run with the throttle at wide open? Fuel filter will usually give you earlier signs of clogging, ie. fuel starvation under WOT.

Mike

car ran perfect no codes on dash pass lock light going off when key is turnt

cked grounds all are good

Did you mess with the intake at all? If the mass air flow meter is unplugged or loose the car will start and die.

Just brainstorming.

-Mike

no i didnt do anything to it before it started doing this . yesterday i drove to several wrecking yards around Laredo went to pet store , etc took Daughter to breakfast . Started and ran fine all day . We had movies to take back to red box and car would not start at that point .

Did you check for codes? Does your car have the zinc post at the fuse box or the brass one? Check fuse 6 and 9 in the underhood electrical center. Check your fuel pump relay, the oil pressure switch bypasses the relay for the initial prime.

Checked all fuses . checked relay , all seem good . checked all that before i pulled tank down and replaced fuel pump. I know this has to be something stupid . but i just cant figure it out . Thanks again to all who have responded . I hope it starts soon

Are you getting voltage at the battery side of the relay? If so, are you getting voltage out of the relay on the gray wire? Did you use the fuel pump test connector...red wire from the relay.

Just thinking,did you have a new key made or maybe started using a different key?
Jim G

Have you checked your oil? After it's started does your oil light go out? Most fuel injected cars I know of will shut down the fuel pump if after it's started and there is not sufficient oil pressure. That could be low oil, bad oil pump or bad oil pressure switch.

All of the above, plus find pigtail, (unused connector on firewall on passenger side, behind fuse box and beside fp relay) and hook it up to the positive side of the battery. if the car starts and runs, the oil pressure switch has gone tango uniform. If no start, swap out the fan relay for the fuel pump relay and try again. If still no joy, check the wiring harness going into the tank.

Hope this helps

Bill

i found plug and hooked to battery still nothing fuel pump relay is 5 prong fan is 4 prong did swap and still nothing

checked all fluids yesterday when this all started . thanks everyone im sure we will sort this out

any and all ideas welcome. i have to get to bed have to figure out some way to work in the morning . I will keep cking post and thank you everyone .

One day I found a new gm pcv valve at my job. I put it on my car and drove to the store. came back to start it and did not start. put the old pcv valve in and worked again. If you did not change your pcv valve sorry.

So you hot wired the fuel pump,. the fuel pump is running ,. and it won't start,.

Uh oh,..i,m surprised there hasn't been 10 replies outlining the opti spark as the culprit,.
cause it just might be,.

was the weather good?

nick

yes weather is good about 105 outside

im going crazy looking for a anything that it could be

i have checked all grounds . i have replaced fuel pump and pressure regulator . i have checked and rechecked fuses . i have done the fuel pump bypass . Checked and rechecked fluids . there just might be a non running wagon for sale shortly.

high79boy wrote:

i have checked all grounds . i have replaced fuel pump and pressure regulator . i have checked and rechecked fuses . i have done the fuel pump bypass . Checked and rechecked fluids . there just might be a non running wagon for sale shortly.

I,m interested,..

Check the connection to the temp sensor on the water pump. I had a loose pin on the sensor on my caprice and it would make a connection, then loose it. The caused the computer to switch between the actual temp and something below zero, which it would try to adjust the fuel mixture for and cause a stall. Pull that cable off and try running it.

When you were in the tank did you check the little 1.5 inch rubber hose between the pump and the metal tube at the top of the tank?

You have described perfectly the exact symptoms of that hose being split. It has happened on three of my wagons now and was a MF to diagnose (the first two times). As much as it pains you to drop the tank again, do it. I have a write on here, it can be done repaired and back in 90 min or less..... I dropped the tank on one of my wagons 6 Friday nights in a row so I got the routine down now, lol.

If you play with the gas pedal when it catches you can sort of nurse it for awhile and the RPMS fluctuate but you can't really drive it?

I just got a smaller outer diameter fuel line and used hose clamps. 20K on the one car, sold another, and about 8K on the third one......no more issues.

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had it happen of both LT1 and TBI cars....same Piece of hose.

check the shift arm. Mine wont start sometimes, I push the gear lever into park and it starts.worth a try.

guess he fixed it. hasn't been back in a week......

damn i wanted to buy that dcm wb4,.

Sproket, good point on the hose. I swapped one out and slit it withins days on time. I replced it with about a14" loop of reinforced fuel line.

No issues since. Those un-reinforced loops that come with the pumps are usually crap.