Hey guys I have a 350 in my jimmy with fuel injected.

I'm having problems to get fuel to come out of the injectors. The pump is new, it's an airtex, from what I've read here about them is that they suck. I have the original pump that works fine but the float is broke so I replaced the whole thing. Well I put the old pump in it to see if it would fix the problem and it didn't, so I know it's not the pump that 's bad. Second I got a rebuild kit for my TBS and that didn't fix the problem, while I had it apart I cleaned the injectors, nothing. Could it be a bad MAP sensor? From what I read about those it'll make you get bad fuel mileage and bad idle, but wont kill the truck, correct? It almost seems like it's electrical but that's where I have a hard time figuring things out.

Any other little ideas you guys can help me out with?
I did a search on this forum and found a few things to check, but nothing that worked thus far.

Oh I should add I got it started the other day (don't know how) and drove it for about 20 minutes before it died again.

 

Alright,few random ideas. 1st off airtex sucks. I went through 4 of em in a few months.

To test a injector i heard you can touch the prongs with a 9volt battery. Not sure if its true or not since ive never actually done it.

Another thing. I dont know if it actually does anything,but when i had fuel pump issues with my 91, I pushed down on the coil pack connections and the pump started working again..Push on em and mark that off.

One more thing im thinking about. I know gm did this safety thing,if the oil pressure unit detects really low oil pressure it cuts off power to the fuel system. I was thinking the pump but it might cut it off at the injectors. Have you swapped sending units in the motor swap? Also check relays on driver side firewall. there is 2 of em side by side. swap them and see if anything changes.

 

This is where a NOID light set comes in handy, I know in Canada Princess Auto stores have a kit for about 10 bucks that comes with NOIDs for many applications. Ive used mine a few times now on different cars. They are going to flash if you are getting injector pulse signals. A fuel pressure check would also be a good thing to know otherwise you are just taking a stab in the dark. Chances are you are having a delivery problem as the injectors are not both going to quit on you. 2 things you might want to buy or borrow - injection pressure gauge and NOID lights - both can be had for about 60 bucks and much cheaper than throwing parts at it and you will have them forever.

I wouldnt go sticking a 9V battery on the tops, most of the electrical signals are sent at 5V and you could do some damage possibly.

Start chasing your wires backwards looking for broken wires, stripped wire casings, and poor connections - wiggle where the wires go into connectors too to see if they are loose.

If you had a bad MAP sensor you would for sure be getting a DTC from it.

 

What's a "DTC"? )

 

DTC == diagnostic trouble code.

 

I can spray starter fluid in the TBI and it'll start, but die in about 5min. The injectors work fine and everything seems normal too. What the heck?

 

Ended up being the ignition cotrol module.