Still runnin' rich...got 'em all stumped.
#1
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From: reidsville,nc,usa
Car: 1989 Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 9 Bolt Borg Warner 3.27 gears
Still runnin' rich...got 'em all stumped.
I got my tax money back and decided to get a Magnaflow hi-flo cat and had the guys install a new O2 sensor while the car was in the air. Sounds good, but I'm still running rich and using gas. I asked the local dealer(s) and they can't figure it out. I also noticed with the new 02 sensor, my scanner showed a big jump in readings. On the road it's up to 1000 mv (1 volt)! They can't seem to find why my ECM is constantly purging the CCP. If it's bad injectors or FPR or tank pressure regulator, that should'nt make the ECM purge the CCP system all the time because it seems like something is telling the ECM the conditions are right for it to purge but never cuts off. This thing is really sucking gas and I've Seafomed it just to do it. For some reason, I don't think it's mechanical.
Ken
Ken
#2
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From: LeRoy, NY
Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: Still runnin' rich...got 'em all stumped.
Did you do a resistance test on the solenoid to see if it's open? Like I said a while ago, the ECM turns the solenoid ON to STOP the canister from purging, and OFF to purge. If the solenoid or the wiring between the solenoid and the ECM is open, the canister will CONSTANTLY purge.
#4
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Still runnin' rich...got 'em all stumped.
If the fuel pump has been replaced it may be that the purge and return lines got reversed at the tank. Easy to do and will cause the CCP canister to fill with fuel and the fuel pressure to be on the high side.
RBob.
RBob.
#5
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From: LeRoy, NY
Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: Still runnin' rich...got 'em all stumped.
This is true. However, the last time he discussed this, he told us that his ECM either wasn't commanding the CCP solenoid to stop purging the canister, or the canister was unable to control the purge, and the ECM wasn't doing anything about it. He hasn't tested to find out why that was/is.
#6
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Still runnin' rich...got 'em all stumped.
This is true. However, the last time he discussed this, he told us that his ECM either wasn't commanding the CCP solenoid to stop purging the canister, or the canister was unable to control the purge, and the ECM wasn't doing anything about it. He hasn't tested to find out why that was/is.
The CCP code in the ECM works. Been proved on many vehicles. There is something mechanical wrong.
Has it even been proven that the canister purge is the real cause of the engine running rich? What happens if the purge line to the TB is removed and the TB port plugged?
If there is another thread on this issue, it should have been added to. Otherwise how are other users supposed to know what has already been done/checked?
RBob.
#7
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From: LeRoy, NY
Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: Still runnin' rich...got 'em all stumped.
OK, but the ECM is supposed to do a purge. And if the purge causes the AFR to be so rich, then why is raw fuel ending up in the canister? And if it is not, maybe then the purge pressure control valve is bad, or the fuel lines got swapped, or the pressure control valve has been removed and/or re-installed backwards, or the lines are swapped at the canister. I'dunno, can't see it from here, can only provide ideas that are possibilities.
If there is another thread on this issue, it should have been added to. Otherwise how are other users supposed to know what has already been done/checked?
RBob.
RBob.
Last edited by Maverick H1L; 02-13-2010 at 04:58 PM.
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#8
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Senior Member
Joined: Oct 2001
Posts: 504
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From: reidsville,nc,usa
Car: 1989 Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 9 Bolt Borg Warner 3.27 gears
Re: Still runnin' rich...got 'em all stumped.
I pulled the vacuum line off the FPR and saw no fuel coming out of the line even when I shook it. I disconnected the line coming off the evap canister going to the TB and plug it. I'm thinking it might be the injectors just need replacing. Since I got the the plenum off, I might go ahead and replace the FPR while I'm there. The purging is still a mystery, but if I eliminate the CCP system altogether, get a vented gas cap, I shouldn't need to worry about gas going into the throttlebody from that route.
Ken
Ken
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Still runnin' rich...got 'em all stumped.
If the stock Multec injectors are in there I would definitely toss 'em in the trash can. Get some decent Bosch injectors to replace them. You will be amazed at how much better the engine will be running.
RBob.
RBob.
#10
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From: Tucson, AZ
Car: 91 Camaro RS
Engine: 3.1 V6
Transmission: t-5
Re: Still runnin' rich...got 'em all stumped.
He's right about the injectors. But any word if the problem has been fixed? I'm having the same problem or somewhat.... I changed out the fuel pump two days ago and next thing you know it back to scare one. I just send screw it and took it to a shop for them to check it out.
Hope you figure the problem out man...
Hope you figure the problem out man...
#12
Thread Starter
Senior Member
Joined: Oct 2001
Posts: 504
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From: reidsville,nc,usa
Car: 1989 Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 9 Bolt Borg Warner 3.27 gears
Re: Still runnin' rich...got 'em all stumped.
Hadn't got it fixed yet. I ordered some injectors 2 days ago and awaiting them to come in. I thought I'd replace the FPR while I was under there. I'm not going to disconnect the fuel lines away from the block as it was a beotch to get the feed line in straight without taking the fuel block off. Ain't going that route no more. I'm just going to lift out the fuel rail and suspend it above the engine to change out the injectors. I had made a temporary block off plate for the steel pipe that come from the EGR to the plenum. Amazingly, the CCP started to purge ON rather than being OFF all the time. Might have something to do with the rich gases coming in from the EGR that causes the CCP not to function right. It's a start and maybe the right track. Time will tell. I'll keep ya'll posted.
Ken
Ken
#13
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From: LeRoy, NY
Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: Still runnin' rich...got 'em all stumped.
When you replace the fuel injectors, undo the 13mm nut on the metal pressure line next to the thermostat housing and the 10mm clamp bolt on the A/C compressor bracket, lift the whole rail out, and swing it out over the windshield washer bottle. Flip the rail over and remove the injectors. Don't forget to relieve the fuel system pressure by disconnecting both the fuel pump relay and the oil pressure switch and crank the engine. Doing it this way minimizes fuel mess.
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