I really hate this truck!!!!!!!!!!!

Problems 4.3 vortec w
-won't start without starting fluid,but runs ok after starting
-bad smell coming out of tail pipe with a thick vapor not oil and doesn't really smell to bad like fuel
-on start up no fuel coming out of injectors
-poor gas milage

Known
- fuel 35 psi key on
-replaced nut kit 10,000 miles ago(I know I should have replaced cpi trying to save $)
-replaced fuel filter 0 miles ago

Questions
-if cpi regulator is leaking how much gas should you see? When my nut kit went out there was a visiable hole with a lot of gas sitting
-if fuel pump is bad how can it run after it starts

I really can't afford to replace items that do not need to be replaced. Is there any way to check for sure if cpi is bad? Also where is the best place to buy as far as price?
AC Delco
Rockauto
GMpartsdirect

Thanks for any help you can offer

You need further information from more experianced folks, such as BlazerLT and others, but I will tell you that fuel pressure seems way too low. Mine calls for 55-60 lbs.(4.3 Vortec, 93 S-10 Blazer) Also, you should have replaced the main cpi when nut kit was replaced. Best places to buy from what I have found is Ebay. provided you have a 4.3 motor there are several people selling cpi units and some are parts companies who sell other parts. Cpi's run anywhere from 200-260 there for GM units. I found a guy who sold me nut kit, injector assy, and plenum gasket for $292, frt paid. You can find aftermarket items at Advance, but I don't think you should. You might also check your coil and ignition module for weak power. And your fuel pump seems a likey problem as well with only 35lbs pressure. See what these other folks think, but that is my opinion.

You need around 60 PSI on the fuel pump that would be the first step to take. It is possible to my knowledge that your vehicle can run on a bad pump once it is started. The major problem is getting it started. You know you have a fuel issue if it does in fact start with starting fluid. Really you should have replaced your CPI when you did your nut kit but maybe all you need right now is a fuel pump. Start there and see what happens. If your CPI is elaking though, when you pull off the upper plenum it should be a shiny color from what I rememebr. I'm not sure as to which side but if the driver side is shiny than it is your CPI and if it is the passenegr side than the CPI. Don't quote me on the sides but I am sure if I am wrong someone will correct me. As far as where to buy parts for cheapest prices I'm not too sure. I know a good many people seem to enjoy Auto zone alot. Me personally I go where the parts are available closest to me.

Problems 4.3 vortec w
-won't start without starting fluid,but runs ok after starting
-bad smell coming out of tail pipe with a thick vapor not oil and doesn't really smell to bad like fuel
-on start up no fuel coming out of injectors
-poor gas milage

Known
- fuel 35 psi key on
-replaced nut kit 10,000 miles ago(I know I should have replaced cpi trying to save $)
-replaced fuel filter 0 miles ago

Questions
-if cpi regulator is leaking how much gas should you see? When my nut kit went out there was a visiable hole with a lot of gas sitting
-if fuel pump is bad how can it run after it starts

I really can't afford to replace items that do not need to be replaced. Is there any way to check for sure if cpi is bad? Also where is the best place to buy as far as price?
AC Delco
Rockauto
GMpartsdirect

Thanks for any help you can offer


First, pull the upper plenum and check for washing. If it is washed at all on the passenger side you have a leaking CPI unit.

Second. 35 PSI is WAYYYYYYYYYYY to low. That's why you're truck doesn't start. Yes, you have either a bad CPI and/or a bad fuel pump. Pressure should be 56-60 at start and 61-65 at running. To determine if it's the fuel pump, pull the upper plenum, if the passenger side is black, you're fine, if it's goldish, replace it.

Now not to say it might not be BOTH the fuel pump and the CPI.

You can get a new CPI at advance autoparts. You can also get the new fuel pump there as well.

I just pulled the pump. Get this there was no wiring harness connecting the float and the pump to the connector. The guy before me had used tape and zipties to hold the wires on the connectors. I bought a new pump and ordered a wiring harness from Rockauto.com. I hope it was the right one there were no pics given. Inside the plenum it looks evenly black a little liquid in the bottom. Going to try the pump and see if I get lucky.

Thanks

You should replace the CPI anyways.

Chances are when you install the new pump with full pressure it will blow it out anyway.

Also, a defective CPI regulator won't always spray.

Got to thinking about it your probably right so I bought a CPI from ebay for $200 not too bad. Quick question though I recieved the fuel pump wiring harness from rockauto (carter part#888-536) it wasn't the right one. Anyone know where I can get one? I just really hate going to the dealer $$$$$$.
thanks

Chances are it isn't the right pump also.

The right pump will have the right wire harness.