Please comment on my spark plug pic - Page 2

dickster · 10-21-2002, 10:19 AM

BGCarrera32

granted but........the 02 sensor only works once warmed up

if its only happening on three cylinders its got to be injectors or ignition??

BGCarrera32 · 10-21-2002, 11:05 AM

dickster...

Right...my point is only that if the car has been running for some period of time in this condition (I don't know based on the info given) that there may have been more problems created downstream by the rich condition. Hence he could change the injectors and still find problems caused by a messed up O2 sensor or a plugged catalytic convertor.

When does the O2 start sending signal? Does it work when the engine or cyl head temp has reached a certain temp?

dickster · 10-21-2002, 11:38 AM

BGCarrera32

Quote:

When does the O2 start sending signal? Does it work when the engine or cyl head temp has reached a certain temp?

yeah, as i understand it.

it seems that the engine was fine until stored 2.5 years ago, so it would be related to the little use its had??

the trouble wouldn't be further upstream would it?? you'd expect all the cylinders to be the same??

gummed up injectors then

ChrisBennet · ChrisBennet's Garage

Here is my reasoning for thinking it might be the fuel injector circuit. I'd want to check it for this reason.
If the picture indicates that 3 cylinders on one side are effected..
Then it is likely something that all 3 cylinder share.
Three cylinders share a cam and an injector circuit.
I doubt it is the cam.

I doubt 6 plugs on one side coming from 2 different distributors all failed to fire.
I doubt 3 injectors plugged at the same tiime, all on the same side.
That leaves one injector circuit. The connection or the driver in the DME may have failed.

You really need an oscillocope to check the injector signal I think.
-Chris

BGCarrera32 · 10-21-2002, 12:14 PM

Thanks for the info...

I guess I missed that it had been stored 2.5 years. Definetly fouled injectors would be my take on it...probably never saw sta-bil in the gas tank...not that it would have done any good after that long anyway

scotsman60 · 10-21-2002, 12:40 PM

Chris,

I think that your "IF" statement evaluates to False because when I look at the picture I see two plugs on the left side are fouled with carbon and one on the right side is fouled with carbon while the others are all clean so I don't think it's valid to diagnoes the cause of the problem to something that affctes the while bank.

Doug

ChrisBennet · ChrisBennet's Garage

Quote:

Originally posted by scotsman60
Chris,

I think that your "IF" statement evaluates to False because when I look at the picture I see two plugs on the left side are fouled with carbon and one on the right side is fouled with carbon while the others are all clean so I don't think it's valid to diagnoes the cause of the problem to something that affctes the while bank.

Doug

Yes, I looked again and I think you are right Doug.
-Chris

kretzj · 11-12-2002, 06:44 PM

I talked with a mechanic friend of mine and he brought up an interesting point. I have been through 3 fuel pumps because the check valve kept sticking. He suggested that I have too high a pressure in the fuel line. He suggested that I check the fuel pressure regulator. But be that, he suggested that I test the return line to make sure it is not blocked. I pulled the hose off the regulator and I could not force any air into it. I removed the hose at the front of the car and verified that the line through the body was clear. I blew into the last bit of hose connected to the tank and I finally managed to create bubbles. After the dizziness subsided, I tested the tube again and it was passing air. What could possibly be in my tank that would block air passage through this connection? Sometimes it was clear and sometimes it was clogged. I looked inside the tank with a flashlight but I could not see that far over. Could this blocked return line have broken 3 of my injectors?

Jon

john70t · 11-12-2002, 10:36 PM

There is a tool that some shops use.. think it's called an injector driver.
Basically the pressure gauge is hooked up to the rail to test residual pressure (if the check valve in the pump is not holding), key turned on to check "deadhead(?)" operating pressure, and then turned off.
This little device is connected to a solenoid. It fires for .5 seconds and the drop in rail pressure is noted. All the injectors are then checked for an even drop in rail pressure.

Considering its happening on one side, it might be a good idea to blow out the lines as well.