Redeasysport

OK your getting somewhere.Did you smell or see gas in the FPR line?

You are correct you relay isn't working and the oil pressure takes over.It sure is beginning to sound like bad injectors to me and or plugged cats as was suggested time to drop them after we get the fuel stabilized.

Anyway It has to be going somewhere best guess I have is stuck injectors if you smell no fuel in the fpr it can drain back through the hose.

Yeppers on the washing the cylinders pull the plugs

red86man

Thanks for the validation, guys. No, there's no gas smell in the FPR, so I guess I should check for open injectors tomorrow - looking for gas fouling on the plugs, and checking for noticable gas smell in the oil, correct?

I think we're finally getting close to fixing my baby - which would be totally awesome!

JAKE

[QUOTE=red86man]:
Conclusions:
- The wire insulation has pulled back on 3 of the incoming wires to the FPR connector, which may be part of the problem.


You've lost me on that one. Wire insulation on 3 incoming wires . . .

Jake

rick lambert

Jake, I think he's saying his Fuel Pump Relay had bare wires-all to typical on our earlier C4s.

red86man

Yes, that's correct - the plastic insulation on 3 of the wire leads coming into the FP Relay connector have shrunken back to expose about 1/2" of bare wire. Consequently, I'm going to pull the individual wires and terminal ends from the connector, clean them with a corrosion remover / inhibitor solution, tin the exposed wires and terminal base with solder, shrink sleeve the exposed wire and reinstall the wires / terminals back into the FR Relay connector. Along with the new FP Relay, that should resolve the issue with the FP not energizing at key-on.

My '86's no start / no run condition has been a compilation of multiple problems - a bad TPS, a bad ICM, challenged FP Relay wiring, a stuck FR Relay, distributor timing out of adjustment, etc. It's been like peeling layers off a bad onion, but I'm finally starting seeing the good stuff underneath.

It appears that I might have an issue with the EGR, as well, but I'll test that later after I resolve another issue. I think the primary problem now is that I have an injector that is stuck open. After my tests last night clamping off the fuel pressure and return lines and still seeing a rapid loss in fuel system system pressure, it became apparent that the fuel is not dumping back onto the tank. The vaccum line on the FP Relay is dry, and I definitely have gas fouling in my oil as noted from the heavy gas smell on my dipstick. I guess that would be indicative of a stuck injector, correct?

Would it be best to pull the spark plugs individually to see which ones are heavily gas fouled, then pull the suspect injectors and test them in a suitable container for the proper conical spray pattern and see if they leak-by after cranking?

Redeasysport

Cheapest and best way to deal with the injectors is to send them to Rich Cruzin to get them cleaned and flow tested


http://www.cruzinperformance.com/


When you get them back change the plugs and oil and you might be suprised.I just had some EGR issues and especially on my year you can plug the egr vacuum line and the engine will run OK with good fuel.I have not seen your EGR so I can't gurantee it will work with yours or not.

red86man

Readeasysport,

Thanks for the info. I'll check out Rich Cruizin's shop for cleaning and flow services after I do some more investigation and testing on my injectors. I'm an eternally curious person and want to do some cranking fuel flow testing from the injectors into a graduated beaker to see what's what.

Redeasysport

I hear ya I am the same way if you test them you will be assured they are the problem.Let us know what you find....

red86man

Roger that.

JAKE

Thanks for that, Rick. I thought he was referring to his Fuel Pressure Regulator.

Jake

red86man

Jake,

It appears I used the wrong acronymn. I edited the previous post to reflect "FP Relay" instead of "FPR" to avoid further confusion.

New Update:
- Pulled the 1-3-5-7 valve cover for further investigation. While cranking, I noted fuel vapor perhaps mixed with a little smoke that seems to be coming out of the view port between the valves on either #5 or #7. Hard to tell exactly which from my angle while cranking.
- I pulled spark plugs #5 and #7 to inspect for excessive fuel. #7 appeared to be wetter than #5 and had some carbon build-up around the base of the metal terminal. Rechecked both FI connectors with noid light and noted proper blinking of the noid light on both connectors.
- Pulled cold start injector connector also, tested it and noted that noid light comes on and does not blink. I'm pretty sure the CSI signal should cause the noid light to blink like the other FIs do, so I'm going to check the flow charts and see where that takes me.
- After pulling the CSI connector, it seems as though the car really wants to kick over now. Almost, but no cigar yet. I also noted that the fuel system continues to depressurize quickly even with the CSI connector pulled. I guess it's possible that the CSI could still be mechanically stuck in the open position even with the connector off, as could be the case with any of the regualar FIs.

I'll keep peeling the onion and see what else lies beneath.

JAKE

[SNIP=red86man]

. The vaccum line on the FP Relay is dry, and I definitely have gas fouling in my oil as noted from the heavy gas smell on my dipstick. I guess that would be indicative of a stuck injector, correct?

Would it be best to pull the spark plugs individually to see which ones are heavily gas fouled, then pull the suspect injectors and test them in a suitable container for the proper conical spray pattern and see if they leak-by after cranking?[/SNIP]

In this case I think he meant to say FP Regulator, not Relay.

I recall reading in my Corvette Shop Manual that to test for a leaking injector(s), you should remove the plenum and runners. Then lift the fuel rails, with the injectors still attached to the rails, from the manifold base. Then energize the fuel pump and look to see if any injector is leaking. You can energize the fuel pump with a jumper wire inserted in the ALDL.

I did it that way on my 86 a few years back when I was re-installing the intake system just to make sure none of mine was leaking.

Also, as I recall in my reading, the rubber pressure and return hoses located a the lower, passenger side, front of the block are the ones to use to block off (squeeze with pliars) when testing for leaks.

Here's how I understand it to works.

If you block off the return to the tank and the pressure STILL drops - since no fuel can return to the tank, the leak has to be somewhere in the pressure line between the tank and the engine or under the hood . In that case, it has to be:

1. The pressure fuel line leading from the tank to the engine compartment, or
2. The Fuel Filter
3. Where the pressure fuel line is screwed into the passenger side fuel rail, or
4. The Fuel Pressure Regulator, or
5. One or more injectors, or
6. Where the return line is screwed into the passenger side fuel rail

If blocking the return line to the tank and the pressure DOES NOT DROP, then leak has to be:

1. The metal fuel line leading back to the tank or
2. The check valve at the fuel pump itself.

So, if your fuel pressure drops with either or both fuel lines blocked off, and if you're blocking them off at the location I indicated (front of engine), then the leak has to be:

1. Fuel line connections at the fuel rail or
2. The fuel rail itself (like having a pin-hole)
3. The fuel pressure regulator
4. The fuel cross-over pipe,
5. The Cold Start Injector fuel connection/line - driver's side rear fuel rail
6. One or more of the 9 injectors.

You're right. Attack this condition by solving one problem at a time. That's how big problems/tasks are solved. Break it down into small, more managable pieces and do one at a time.

Hang in there, we'll get it.

Jake

red86man

Great info dump, Jake - thanks! Time to break it down and see what's up.

Redeasysport

Nice post Jake.Well thought out.

red86man

I took my latop outside (60'F and sunny here in the Rochester, NY area right now) so I don't have to run in and out of the house to post. Gotta love wireless networking...

Anyway, here's a few new wrinkles:
- Pulled the Air Filter assy. off the front of the intake and disconnected the MAF sensor. In doing so, I noted about 3 or 4 oz. of raw fuel coming out of the flex duct and the bottom of the MAF sensor is wet with gas. That can't be good.
- Cranked the engine after Filter Assy. removal and noted spurts of fuel droplets, air and smoke coming out of the intake of the throttle body. That's not good either.
- Pressed the accelerator all the way to the floor to initiate Clear Flood and further cranking almost caused the car to start. Smoke / fuel vapor also continues to blow out of throttle body intake while cranking in Clear Flood mode.

Interesting, huh?! Your thoughts?

CFI-EFI

Close. To simplify, I will leave out threaded connectors, the filter, and other, fairly easy to observe points of leakage. I'll concentrate on the three "hidden" sources of leakage, the injectors, the regulator, and the fuel pump check valve. First, make sure the fuel pressure regulator isn't leaking fuel into the vacuum line. As Jake's, first step, clamp the return line and pressurize the system. If the pressure drops, it is escaping through the injectors or the fuel pump check valve (which is in the inlet side of the system). If the pressure holds, the injectors and the check valve are holding. It must be the regulator.

Next pinch off the inlet line while the system is pressurized. If the pressure drops, it can only escape through the injectors or the regulator. One of which would have been eliminated during the first test. If the pressure holds, the regulator and the injectors are good, and it has to be the fuel pump check valve. Too easy.

RACE ON!!!

[NOTE]The RED text in the quote comments add by me.

jmrl98

When my AFPR diaphram went south, it wouldn't start, and guess where I had fuel? All the way up to the air cleaner box! Fuel rail, crossover pipe, or your FPR like Jake stated are likely targets, I think. Good luck, you're knocking on the door!

JAKE

I've engaged in this back and forth on this specific issue before so I won't revisit it again. Too many counter-punchers to contend with, so I'll just concentrate on helping diagnose the problem.

Now, if you found gas in the intake filter area and MAF and see fuel mist escaping from the TB AND since your fuel pressure regulator is dry, this points to injector(s).

I'd now pull the fuel rails with injectors attached and see which one(s) is/are leaking.

Also, chances are that raw fuel has coated and contaminated the MAF sensor wires, so I'd pull the MAF and use a spray cleaner - something designed as an spray electric parts cleaner that leaves no reside - to clean them. I've used brake and carb cleaner in the past, but spray designed specifically for electronics is best. Be sure to turn the MAF upside down to prevent any spray cleaner from entering the electronics in the base of the MAF.

I'll bet that when you check the injectors you'll immediately see the cause.

Keep us updated.

Jake

Jake

red86man

Jake, CFI-EFI and jmrl98,

Thanks for the excellent feedback and tips. I have noted a couple symptoms of my no start problem, which are as follows:
- Fuel droplets, vapor and smoke coming out of my throttle body instead of air getting sucked in. Hence, the 3 to 4 oz. of gas that poured out of the flex duct upon removal.
- Fuel in my oil - probably at least about 1 quart according to my dipstick.
- And, aside from these symptoms, no fuel fouling in the vacuum line to the FPR.

Logical troubleshooting would lead me to look specifically at what is common to both the air intake system (which has now become an air exhaust system) and the fuel system. This line of thinking makes me suspect the FPR as the potential problem component. Maybe an FPR diaphragm meltdown as jmrl98 shared with us, perhaps?

The flex lines for the fuel pressure and return seem to be tucked way under the belt idler to the bottom right of the front of the engine - one on top of the other. When I clamped the lines last night, I did so at the top cover of the fuel sending unit, which is more easily accessible to me. Given the fact that no fuel is leaking out under the car from either line, nor is there any noticable external fuel leakage anywhere else - it all appears to be leaking into the engine, then shouldn't I be able to clamp the tank lines for pressure testing. If not, then which line in front is fuel pressure and which is fuel return (from top to bottom)?

AGENT 86

Sounds like funky valve timing to have fuel blown backwards into the plenum, TB, duct and MAF