Help!!!!! I cant figure this overfuelling issue.

[IndigoMKII]

THanks for your response Indigo but we said the exact same thing a different way. I just gave the color of the second wire. I just thought it was understood about the yellow black white wires. sorry my fault on not being clear. 2. come to find out cylinder 5 and 6 injector wires were switched. 3. The injectors were sent off a month ago to rc engineering to be check and balance. they are fine. 4. I have an aeromotive adjustable fuel pressure regulator and I dont know if the diaphram is bad. I have been told that they will go out and overfuel but I am afraid if I take apart that I may have to buy a new one. Its only two years old. What are your thoughts? The base pressure is set is the 33 psi vacuum line on. but the pressure drops as soon as the car turns off. so just not sure on a ton of issues. I dont know if its cold start injector stuck open, fuel pressure regulator, or check valve in the walbro fuel pump or if the switch injector wiring will fix it. I put the clips back right have not had time to try to crank it. wife and kids are off all week with me. I hope you understand. thanks for the response and sorry for not being clear

I see what you said now, sorry I misread it.

To see if it's the cold start injector, just cap the fuel line on the rail going to it. I could see 5 and 6 being backwards over fueling your engine, you've got fuel being dumped on the intake valve while it's shut so it's not entering the combustion chamber as a vapor and just puddling on the piston. It's just going out as raw fuel on the exhaust stroke. I'm sure some of it is being burned but not enough to burn it all.

 

[jg5899]

Not sure how this is possible, when an injector went bad on my friends supra, he had a hard time keeping it running..

If the injector was bad then it wasn't firing at all, mine were just firing at the wrong time. 7m's run batch fuel.

 

[suprahero]

Bernard, if you need any parts after finding out what's wrong, let me know. I have alot of 7m parts that I bought from Andrew. Anything I have is yours if it will help you. I don't have a spare fuel pressure regulator, but I can send you mine if it will help you. I wish I knew what was causing your problem, but I don't have a clue. I would have thought it was an injector or two, but you said they were just cleaned and checked for proper flow so it can't be that. Let me know if you need anything., Jay

 

[7mboze]

jay thanks I will be hitting you up if I need any 7m parts. thanks for the offer. You and these guys on this forum are just awesome.!!!!!!!!

 

[supraguy@aol]

Well?
Did you check injector plugs?

 

[7mboze]

yes supra guy I check the injector plugs 5 and 6 cylinders were switched. The car did crank up better and quicker and it did not backfire. but its still overfueling. THis is what I did. Right after It ran for like 15 secs before flooding out, I immediately took out all spark plugs to look off into the whole. #6 cylinder was the only one with a puddle of gas on top of the piston. The rest were burned as normal. So I put everything back on and left the #6 cylinder spark plug out of the car. The car ran better on 5 cylinders than it did 6. So at this point. It looks like injector 6 is the culprit. This is confusing because I just sent them off to rc engineering close to 2months ago. Tomorrow I will switch injectors 5 and 6. if cylinder 5 floods then I will conclude its the injector. Any suggestions supraguy?

 

[IndigoMKII]

The car ran better because it wasn't trying to push a dead cylinder, are you positive number 6 plug is firing?

 

[suprahero]

Great question Indigo.

 

[7mboze]

Well I have to work on the car by myself alot so nobody to watch the plug. but I did put a spark plug light into the #6 coil wire and spun the engine over. The spark light was very active. Now I can cant spark on the plug. But I bought new plugs before i started yesterday. they shouldnt file that quick. Thanks for response I will recheck.

 

[thevork]

You can pull the spark plug wire and hold it near the metal chassis of the car while the engine is running to check if there is a spark ?

 

[IndigoMKII]

You can pull the spark plug wire and hold it near the metal chassis of the car while the engine is running to check if there is a spark ?

If you try to get a spark on the car in the engine bay, PLEASE disconnect the open injector.

 

[Rollus]

Hi,

A blocked injector may cause overfuelling.
I don't know if it's a reliable test, but here is what I used to do to test if an injector stay open:
At idle unplug an injector, if idle goes rough or die, injector is not faulty, else if no change it may.
For the cold start injector, pinch the tube or replace it by a cap.

How are your plugs after removal? (Wet, carbon, etc..)

++

Rollus

 

[7mboze]

only the number 6 cylinder plug is soaked. and fuel is on top of the piston

 

[toytech]

Fuel or oil? Washed out rings? Compression test? Fuel psi leak down test?

 

[IndigoMKII]

fuel psi leak down tests dont always help. the fuel pump may not be able to hold back pressure.

 

[7mboze]

thanks guys a friend of mine loaned me an injector today. so I will switch it out to see if it still does it tomorrow. I have not done a compression test because the motor has less than a l000 miles. I will get around to compression as last resort. THanks for responses all you guys have been most helpful.

 

[supraguy@aol]

thanks guys a friend of mine loaned me an injector today. so I will switch it out to see if it still does it tomorrow. I have not done a compression test because the motor has less than a l000 miles. I will get around to compression as last resort...

Compression test is a last resort?
VS. pulling everything to change to a borrowed injector?
Oh well, to each his own. Let us know how it goes.

 

[MDCmotorsports]

Didn't see the question asked, but since you had the head redone, are you sure the cams are timed right? CPS is 10-12 deg with test wire in?

 

[7mboze]

no compression as last resort because I put 2000 dollars in the bottom end alone not including the head and drove it 600 miles and the copper gasket blew. Its just unlikely. plus compression or not fuel shouldnt be sitting top of the piston. IF its a deal cylinder it will show lol..... thanks supraguy

 

[supraguy@aol]

ok.


ps- you used a copper gasket?