I'm stranded about a thousand miles from home. Rapid City South Dakota. 1995 Winnebago P30 chassis, 454 with throttle body injection. I've got zero fuel pressure. I think it's the fuel pump went out. Huge 70 gallon tank.
Question, can I scab in an extra inline fuel pump and have the new pump suck through the old in-tank pump? I have limited tools with me. We were just beginning our vacation. Trying to get back on the road ASAP.
I had bought an in line pump years ago at Summit that I used on a Camaro that had an in tank pump. It was possible for that but it was a 2.8 V6. Not sure about a 454. I think though it would be possible for your application.
Don't know if this will help or not.
If the pump will draw through (dunno) an e2000 inline will be simple to scab in in line
Are you certain theres no fuel pressure? The regulator is built into the tbi with no simple way to check pressure.
Not sure what pressure you need, but the pump for an '88 Ford F-250 with a 302 and fuel injection makes something like 45 psi, comes with the fittings to mount it in-line on a framerail or something, and is in stock at almost any parts store. It's my go-to "OMG I need an external pump that makes fuel injection pressure and I need it now!" option.
Oh, and assuming the in-tank pump is dead and not clogged, you'll probably be able to get away with sucking through it.
Also, injector pulse is controlled by ignition control module. Theres also fuel pump relay, with an ovverride for oil pressure. Have you checked relay and fuse?
No sound of pump coming on when key turned on. Engine will run on fuel dumped down the throttle body.
I cracked the fuel lines lose at throttle body when cranking. Nothing is getting up there.
I've no way to test relay
I've checked all fuses. There's one that keeps blowing, but the internet says it's only for emissions.
Can you swap the horn relay in place of fuel pump relay on the motorhome like we do on trucks?
Was emissions fuse popping previously?
Sounds like either electrical to pump or pump itself.
Easy button is probably the ford pump tom reference (should be the same e2000 i suggested) and straight wire through a toggle. Just make sure you use the correct line. And i don't remember which side is return vs pressure on the 454 tbi. But i do know backwards gets ugly.
Indy "Nub" Guy said:I've checked all fuses. There's one that keeps blowing, but the internet says it's only for emissions.
It's the red 10 amp that's labeled "ECM-IGN" edit to correct label
oh man that fuse certainly seems related and important. Will start searching wiring diagrams for you now.
I know this is strongly not advisable, but have you tried upsizing the fuse just to temporarily prove the concept and see if it'll run? Just to make sure that you're not dealing with 2 separate issues...
I'd be looking squarely at the fuel pump and this 'override' relay and their associated wiring. You should be able to hear and feel the relay click when it activates.
In reply to Robbie (Forum Supporter) :
Thanks for that. Does it apply to my 1995 P30?
That shows 1990, with a carb. Not the throttle body injection.
I agree that that fuse sounds important. If you have a spare fuse to throw at it, with the help of a lovely assistant I would identify the fuel pump relay(s?), and then have them pop in the a new fuse while you have your hands on the relays. Even though it will blow, you'll probably get to hear the relays click as the fuse pops if they're any good.
Take a look at the injector wiring. Found a reference that the fuse may power the injectors themselvs, and i KNOW ive seen failed wiring on them.
dunno if the pics I posted above are correct or not, they do show the wrong years but may be similar. I also found this. It would seem there is an oil pressure sensor and a relay to check.
I am replying to this for all users who may currently be struggling with the NO FUEL being pumped to the TBI injectors. I noticed a lot of mechanics giving all sorts of answers like cut this and add that..
The fuel in a P30 works like this.
Turn on the key
this triggers two items 1 the ECM and 2 the oil pressure switch.
You need both to register to start the fuel pump.
If you think your fuel pump is out try
- Turn key and put ear to gas tank or a funnel in the filler neck to listen for the pump to start
- If you hear it check the fuel filter for a clog
- if not move on to replacing the oil pressure switch. This is 30 bucks and takes like ten minutes to replace yourself. NOTE: THE OPS only allows for the starting of the fuel pump in the first 2 or 3 seconds of the ignition process.
- If this doesn't kick off your fuel pump then move on the replace the fuel pump ECM, This is the electronic control module or Fuel pump relay located on the left wall behind the A/C compressor. Again 25-30 bucks. a little harder to get at but as cheap fix.
- If these do not make the pump work and if you can find the wires, try to hot wire the fuel pump with a 12 volt battery and wiring to allow you to do this without cutting your wires.( Quick Splice Wire Terminals T-Tap Self-stripping with Nylon Fully Insulated Male Quick )
- if the pump starts in any of these try's, you probably have a clogged fuel line.
- If all these fail to start the fuel pump , it is probably bad..
I am not a mechanic and learned this the hard way. . Hope this saves you money.
from here: https://www.irv2.com/forums/f258/chevy-p30-fuel-shut-off-switch-438136.html
In reply to Dusterbd13-michael (Forum Supporter) :
Looks good?
Reply to Wonko,
I'll give that a try
Look at the manifold directly under air cleaner base as well. But the in body side looks good, which is where they normally fail.
also seeing stuff about the neutral safety switch? Can you start the van (or not blow the fuse) in neutral?
https://www.justanswer.com/chevy/cqj9f-ecm-ign-fuse-keeps-blowing-1995-chevy-chasis.html
Robbie (Forum Supporter) said:also seeing stuff about the neutral safety switch? Can you start the van (or not blow the fuse) in neutral?
https://www.justanswer.com/chevy/cqj9f-ecm-ign-fuse-keeps-blowing-1995-chevy-chasis.html
Robbie. You are my Hero! Thank God for your help. It started in neutral !!! We will be able to resume our vacation.
A million thanks to all you guys for your help..
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