Installed a AFPR and no change.
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Installed a AFPR and no change.
I got around to installing a Holley AFPR and no change. My 86E has been running rich ever since I got it running again. The injector that were in it were bad so I installed 24 lb Accel injectors. Still running rich and have done tons of troubleshooting to find the problem. I have (over the last 4-5 months) narrowed it down to either too much fuel pressure (stock FPR at 40 psi vac on/46 psi vac off) or needing my chip tuned for the injectors. Well after yesterday looks like the chip is next. I got the fuel pressure down to 34 psi vac on/40 psi vac off and it runs and smells the same as before. I hate to lower the pressure anymore and am really unable to because the adjustment dial is touching the plenum. I guess I will be sending my chip for some tuning.
I was able to run the TunerPro RT for a few minutes but it keep losing the ALDL connection, so really haven't had time to try again.
Any suggestions or comments welcome.
I was able to run the TunerPro RT for a few minutes but it keep losing the ALDL connection, so really haven't had time to try again.
Any suggestions or comments welcome.
Race Director
Joined: Jun 2004
Posts: 13,961
Likes: 707
From: WI
Mine has been rich to. I have a ticking sound that I thought was the injectors, it isn't, I unplugged each injector and the ticking did not stop. Must be a lifter or rocker. Does yours tick at all? When you reset the IAC and set min. idle speed, can you set it down to 550 RPM? Mine wouldn't go lower then 1200. Extra fuel from the ticking, or vacuum leak. Does yours have any extra symptoms? Mine runs like a champ but has a slight lope to the idle.
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by Aardwolf
Mine has been rich to. I have a ticking sound that I thought was the injectors, it isn't, I unplugged each injector and the ticking did not stop. Must be a lifter or rocker. Does yours tick at all? When you reset the IAC and set min. idle speed, can you set it down to 550 RPM? Mine wouldn't go lower then 1200. Extra fuel from the ticking, or vacuum leak. Does yours have any extra symptoms? Mine runs like a champ but has a slight lope to the idle.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Been awhile, kinda wondered how it was going.A couple things, did you ever check your distributor? I have to admit, I can't remember about your exhaust..headers? If I remember correctly your BLMs were in line weren't they?
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by rick lambert
Been awhile, kinda wondered how it was going.A couple things, did you ever check your distributor? I have to admit, I can't remember about your exhaust..headers? If I remember correctly your BLMs were in line weren't they?
Originally Posted by Aardwolf
Hmm it's sure gonna be good when these are fixed!
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
New injectors, new AFPR and you're still running rich....time to go back to the 02 circuit. And I know that some places (shops) are addiment about which brand of 02 sensors they will and will not use. This may just be a case of a **** poor 02 sensor.
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by rick lambert
New injectors, new AFPR and you're still running rich....time to go back to the 02 circuit. And I know that some places (shops) are addiment about which brand of 02 sensors they will and will not use. This may just be a case of a **** poor 02 sensor.
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Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Originally Posted by rick lambert
New injectors, new AFPR and you're still running rich....time to go back to the 02 circuit. And I know that some places (shops) are addiment about which brand of 02 sensors they will and will not use. This may just be a case of a **** poor 02 sensor.
I didn't look at your combo but IMO if you start heading down to low in FP you will sacrifice the spray pattern/atomization of the injector, not to mention you will start noticing other things on the scan. I would be looking to get it right at around 44-45psi. w/vac. removed. Also all changes should be done in small increments so you can see the effect.
You might want to go into the control panel on your lap top and make sure you are getting the comm port you want. TP rt will automatically find the hardware when you get it right. MO
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
On the scan the O2 sensor numbers stay between.75-.85v and they do bounce around but stay on the rich side. I have a stock engine/chip with exhaust mods and 24 lb injectors. I will have to go back communication port...sometimes it stays connected and sometimes it comes and goes. 
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Originally Posted by RRT vette
On the scan the O2 sensor numbers stay between.75-.85v and they do bounce around but stay on the rich side. I have a stock engine/chip with exhaust mods and 24 lb injectors. I will have to go back communication port...sometimes it stays connected and sometimes it comes and goes.
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by mseven
IF it is only staying between .750 and .850mv. that would indicate an issue. It should be bouncing rapidly between 100-800mv.(aprroximately depending on whats done etc.) and not staying in one area.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
I'll hook up the scanner in the morning and get back..but, to me it's very hard to just look at the 02 on the scanner and say good or bad, simply because it does jump around so much.That's why it's important to look at BLMs (long term fuel trim). We should also say..you've changed the ECM. Basically you've almost replaced everything that would contribute to a rich condition. I know you changed the 02, but I also know some shops refuse to use some brands because they say the calibrations are off..don't know about Bosch, they've always been a good company. I just have to believe with new injectors,new AFPR, different ECM...that it has to come back to the 02 or 02 circuit.
At work now, then a party tonight.
At work now, then a party tonight.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Originally Posted by rick lambert
I'll hook up the scanner in the morning and get back..but, to me it's very hard to just look at the 02 on the scanner and say good or bad, simply because it does jump around so much.That's why it's important to look at BLMs (long term fuel trim). .
Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Yeah, the new injectors in Feb. (ran the same with unknown lb injectors previously), a different 88 ECM 2 months ago, and a AFPR as of yesterday. I don't think the O2 sensor is faulty or wiring is bad/grounded (no O2 sensor codes at all/ever with either ECM). It's done the same with 2 different ECM's, one being a unknown burnt chip. I notice the o2 sensor reading going all over the place but staying on the rich side of the ECM readings. Never have I witnessed it below .45v and the exhaust will burn you eyes and soak your cloths it's so rich. I have uses two different O2 sensors in the last few months and one being a heated sensor and same thing, except I didn't run a scan with the heated sensor in. The one in it is about 3 months old but not alway full proof being new..you know how it goes. I contacted Alvin (supporting tuner) and he tells me that when you increase injector size you will need to progam the chip for the increase and a AFPR is just a band-aid solution. I'm really stuck on this one and the tune sounds like the next step. Been working on it so long it's becoming a bad habit...at least the wife thinks so.
Thanks guys.
Thanks guys.
