Okay so the other day I changed my fuel filter. Haynes says to relieve fuel pressure by removing the fuel pump fuse, which is *supposed* to be near the battery, but of course wasn't. So i undid the two injector fuses and tried to start the car. the pump primed, but the car wouldn't start, just turn over. So I change the fuel filter and also the plugs, and to my surprise the engine just turns over but doesn't start.

I've got 45 lbs of pressure to the fuel rail (tpi), i've got spark, and i know the filter is in the right way. I'm guessing the problem is with the injectors or hopefully not the ECM. So far 3 good old boys and one GM mechanic are baffled. You fellas got any good ideas? I'd really appreciate it.

 

re-check your fuses? Could have blown one. I always released fuel pressure at the schrader valve on the rail

 

i checked the fuses and didn't find any problems. Thanks

 

Some cars are equipped with some kind of automatic fuel pump shut-off switch.....BUT that might be only a newer car thing.

Just for reference, pulling the injector fuses to relieve fuel pressure isn't going to do it. Lol, I suppose you found that one out though. Like Dale said, most people do it through the Schrader valve...but that's a good way to get soaked in gas first. And for the life of me, I can't remember where the fuel pump fuse actually is. A lot of people have had a hard time finding it though.

Did you try disconnecting the battery completely to reset the ECM? Maybe you tripped some kind of failsafe or something that shut the injectors off.

 

The FP/INJ1 and INJ 2 fuses in the fuse panel are for the FUEL INJECTORS only. The fuel pump fuse is on the opposite side of the engine compartment from the battery, one of two bolted onto the frame, but the easier way is to grab a paper towel or clean rag and hold it over the Schrader valve at the back of the fuel rail as you depress the pintle inside as to avoid the gas spray.

Or, you could get up early in the morning and change the filter. There is sure to be no pressure in the lines after the car has sat for 12 or so hours...

 

HMMMMMMMMMMM!!!, I wonder what the letters FP in FP/INJ2 stand for!! Also, that fuse on the right hand side of the engine bay that is supposed to be for the fuel pump. It also controls battery power to the ECM at pin B1 and C16.

 

Ok, off-topic, but I have to ask....DUDE, where do you get all these diagrams and flow charts? Every post I see you make, you've got a diagram or chart for it! It's maddening!

 

Yeah, but he is having problems getting the engine to run again and I figured he forgot to put the two injector fuses back in... And I don't understand why GM labeled the second INJ fuse as also being a fuel pump fuse... In the two wiring diagrams I have just looked at, it has nothing to do with the fuel pump...

 

Here is a abreviated schematic of the fuel injector wiring.

 

Kind of off topic, but having to do with the ECM nonetheless...
According to the Haynes I have, there is an elec connector for the ECM that I can just unhook any time I like to reset the ECM. Is this true for my 87, and if it is, where is it? I hate unhooking the battery and resetting my stereo just to reset the ECM, or undoing the panel and unhooking the wiring from the ECM to do the same thing....

 

To Nixon1, it's a trade secret but I have the GM service manual scanned into my computer so I can just print out the pages I need or refer to my laptop.

 

You can pull the ECM fuse, on the pass. side bolted near the fender.. Always worked for me.

Trickster....... Hahaha....niiiiiiiiiiiice.....

 

There are two fuses there, they are nearly identical the last I looked... which is it?

 

Thats because they are identical, one goes to pin "B1" and the other one goes to pin "C16" on the ECM. Some models like yours had two of them.