Help! No fuel to the TPI

[Gobbles]

As some might know, I've been having trouble with my 90 not starting or starting and having a rough idle and then shutting down.

Well today I took off the air intake section, not to include the TPI and had the wife spray engine starting fluid in the TPI. Well it starts like a champ with the starting fluid in the TPI, but once it burns off, then back to crap. I'm thinking I'm not getting fuel to the TPI. What should I check to make sure everything is hooked up or can anyone point me in the right direction? Thanks for the help... If you have questions, about what is going on that may clarify with your assistance, please ask.

Thanks

Tim

 

[GO_VETTE]

possible things to check.
1. Idle air control valve
2. oxygen sensor
3.fuel pressure regulator
* if the car starts and can run for a 5 seconds WITHOUT starting fluid, fuel pump is MOST LIKELY good*
if you have to start intially with starting fluid, then I would check fuel pump, fuel pump relay.
you can also inspect to see if any fuel around fuel rail, sides, front, and with flashlight (behind the plennum) to see if any fuel leaks.
sometimes O ring seals can go bad.
good luck.
proper tools help.

 

[Gobbles]

possible things to check.
1. Idle air control valve
2. oxygen sensor
3.fuel pressure regulator
* if the car starts and can run for a 5 seconds WITHOUT starting fluid, fuel pump is MOST LIKELY good*
if you have to start intially with starting fluid, then I would check fuel pump, fuel pump relay.
you can also inspect to see if any fuel around fuel rail, sides, front, and with flashlight (behind the plennum) to see if any fuel leaks.
sometimes O ring seals can go bad.
good luck.
proper tools help.

Idle Air Control Valve?
Oxygen Sensor?
Fuel Pressure Reg?

Car runs great without any engine fluid for about 5 seconds. If I try to give it any gas, it stallsout. I'm curious if it has anything to do with timing or Fuel Injectors. Not sure about injectors because I measured the pressure at the fuel rail and it was in tolerance. Recently had the manifold gaskets replaced because they blew and had to get them taken care of for state inspect. I am curious about the fuel regulator because I'm not sure if the engine is getting enough fuel into the injectors, or however it works. Plus they are only $60. Along with noticing that one of the eight spark plug wires are broke/spliced. So I've got to replace my plug wires which doesn't look fun with all that extra space around the engine compartment.

Well thanks for the info and I'll have to take a look at those and see what my FSM says about them and how to replace them.

Tim

 

[bill5674]

you gotta hook up a fuel pressure gauge,to the fuel rack. anything else is just guess work.to keep beatting the old dead horsy...get a factory service manual.but in the mean time,you gotta know what the fuel pressure is.

 

[Gobbles]

you gotta hook up a fuel pressure gauge,to the fuel rack. anything else is just guess work.to keep beatting the old dead horsy...get a factory service manual.but in the mean time,you gotta know what the fuel pressure is.

I measured the fuel and got 42-43 which is within tolerance for the L98 model that I have under the hood. Hooked up the gauge to the rail and found that measurement. I dont see any leaking fuel that would cause the problem as of now. Thanks for the help if you've got any ideas, that would be great.... Thanks again....

Tim

 

[bill5674]

hey tim ,looks like we posted at the same time.did you check the resistance at the injectors?

 

[GO_VETTE]

there is a gauge which can be attached to fuel rail. You will get the readings from here about your fuel pressure reg.
in most cases it sets between 37-45 lbs.
does the car idle at all, if you dont press gas?

 

[Gobbles]

hey tim ,looks like we posted at the same time.did you check the resistance at the injectors?

Nope, dont know how to do that one. I was just going to replace the injectors if a worst case scenario. I know it will be a pain to do that, but I'm sure after 150000 miles its probably time to replace them.

I dont know if you guys know, but I was driving it fine the other day after I got the manifold gaskets back and then "bam" if I pressed the gas, she would die. I had to idle her home basically. I think once she warmed up she got sick some how.


Thanks for the help thus far....

Tim

 

[GO_VETTE]

I agree w/ bill. guessing can just make thing aggravating. but best is to check gauges.
just make sure your exhaust (cat convertor) is not filled with broken cracked up fiberglass.
bad EGR valve can do this too. I had this problem on a Ford Crown Victoria 4.6L.
I have seen my friends car, with similar situation--

 

[Gobbles]

there is a gauge which can be attached to fuel rail. You will get the readings from here about your fuel pressure reg.
in most cases it sets between 37-45 lbs.
does the car idle at all, if you dont press gas?

Car idles fine without the gas for about 5 seconds then shuts off.

 

[Gobbles]

I agree w/ bill. guessing can just make thing aggravating. but best is to check gauges.
just make sure your exhaust (cat convertor) is not filled with broken cracked up fiberglass.
bad EGR valve can do this too. I had this problem on a Ford Crown Victoria 4.6L.
I have seen my friends car, with similar situation--

I was under the car yesterday with a cutting tool trying to cut the entire exhaust off. After cutting yesterday, rust flakes were coming from behind the cat in flakes. I want to remove the exhuast and see if it changes anything before I do anything to the F.I. system. I've had a few people say the cat could be clogged which is why the manifold gaskets blew, so I've cut holes in the pips under the car.

Also got some back-fire the other night, but not really sure what that caused that...

Thanks guys for the help this far


Tim

 

[GO_VETTE]

well, if your catalyc convertor is bad and need replacement, i think drilling a hole into it and cleaning it would not harm for troubleshooting purposes.

HOWever, I am a big Supporter of Catalyc Convertor. I would be emissions compliant.
I believe your car has 2 mini cats on the Y pipe. connected to 1 bigger Cat, and then another Y pipe to mufflers.
I bought my Vette, some kid had gutted the Cat Conv. the ride was so horrible. literally breathing Carbonmonoxide.
I replaced it w/ a DYNOMAX and the car runs better.
My entire exhaust, Cat, Y pipe, 2 mufflers costed within $550.00.

 

[rlg]

According to what I read the EPA approved the removal of the pre cats at the y pipe.

That Y pipe W/O the pre cats is on ebay for about $220.00


Lose 1 b and the s and we have the same name. (if that is your name).


just a guess but the IAC valve could be stuck .
Mine was stuck all the way out . it would start but would not idle. I could keep it running using the pedal. replaced it and all is well. You can clean them and it might work.

check the onms on the injectors , very few fail mechanically.

 

[toptechx6]

Read this thread from "another" forum pay particular attention to post #5, the guy knows what he is talking about.

No power to injector, causes? - Corvette Forum

 

[milehigreg]

See the thread " Hard Start/No start Troubleshooting Log" The easiest check is the injector resistance check. May as well start there. The guy in the 5th response in the above referenced thread is dead on. One bad injector causes the ECU to shut down after the engine catches.

P.S. By the way, the Factory Service Manual gives no indication that that is the case.