Factory Five Racing Forum banner
1 - 11 of 11 Posts

·
Senior Member
Joined
·
715 Posts
Discussion Starter · #1 ·
Car is running a bit rich, and it idles at 1.5k and sometimes fluctuates between 1k and 1.5k.

The engine started life as an SD '87 302 HO that had no check engine light glowing when I took it apart. It's now .030 with an E cam. I converted it to MAF using an A3M1 ECM. I also added an Explorer intake, and TB - adapting the '87 TPS. Fuel rail and injectors are from the 87.

I pulled the codes (several times) and this is what I get:

2 KOEO codes:
67 - Neutral safety circuit failure.
I eliminated the transmission neutral switch. Should I have connected the wires or isolated them?

82 - Air management 1 circuit failure (AM1/TAB)
I've yet to check the connections on this one.

3 CM codes:
14 - Two or more successive erratic Profile Ignition Pickup (PIP) pulses occurred, resulting in a possible engine miss or stall.
Should I be concerned about this?

33 - EGR valve opening not detected.
I have Ryan's EGR eliminator thingy so I'm not sure why it's throwing this one. I can live with it regardless

41 - HEGO sensor circuit indicates system lean (right side).
Is there a way to check O2 sensors?

Thanks for any advice you can throw my way.

[ October 31, 2007, 08:13 AM: Message edited by: Steve in 20186 ]
 

·
Banned
Joined
·
7,701 Posts
I also have codes 67, 82, and 33. I've eliminated the neutral safety switch (but kept the clutch safety switch), removed all the smog pump bits, and removed the EGR, but didn't "trick" the computer with the resistors for any of it. I don't care that the codes are sitting in the computer, because the car drives just great.

Code 14 sounds like a problem with the distributor guts.

Not sure about 41. Ping Narve; he's an EFI guru.

Greg
 

·
Senior Charter Member
Joined
·
3,086 Posts
Agree with Greg, for now you can ignore 67 and 82. Although to perform the Engine Running test you will need to remove 67. The EGR eliminator will set Code 33, so that is working correctly.

You will get a 14 if you unplugged the distributor with the engine running. Otherwise the EEC might be losing the PIP signal periodically, go over the wiring and connectors to be sure everything is tight. For now I would try a reset and see if this one returns.

Code 41, since you only have an O2 issue on 1 side, to check the O2 just swap the O2's side to side, reset the computer (remove all power for a few minutes), run the car and recheck the codes.

If an O2 is old and lazy it will tend to fail lean. Some other possibilities are a vacuum leak, exhaust leak or a missing cylinder (burned plug wire or such).

I have rambled a bit so feel free to ask questions.
 

·
Senior Member
Joined
·
715 Posts
Discussion Starter · #4 ·
Thanks guys. This has given me a perspective on things. I think I'll start by swapping the O2's, resetting, and see what comes back.

I guess I forgot to mention that I have cats and air pump on this. No EGR though. That said, what are the consequences if the TAB is failing - will it pump too much air to wherever the TAD is sending air?

Thanks.
 

·
section 8
Joined
·
5,136 Posts
I vote for a vacuum leak , with efi lean is rich and vice versa . 20+ years in the business, Ive never changed a Ford o2 for failing unless the car had popped head gasket and ran coolant over it.
hmm I'm old and lazy , but not "lean". Follow Narve's advice he's bailed me out a few times, Bob
 

·
Senior Charter Member
Joined
·
3,086 Posts
I think the failed TAB should just divert the air to atmosphere, but I'm not sure (never messed with it). Check the resistance of the TAB solenoid, should measure around 75 Ohms(?).

If it is diverting air into the exhaust, then you would get a lean condition. However you would see this on both sides.

Don't worry Bob you would probably call me young and lean, but I'm still lazy.
 

·
Junior Charter Member
Joined
·
815 Posts
TAD = Thermactor Air Divertor
TAB = Thermactor Air Bypass

TAB vents to atmosphere, TAD between the cats and the heads. TAB is the first one after the air pump.
 

·
Senior Member
Joined
·
715 Posts
Discussion Starter · #8 ·
Originally posted by Lurker:
TAD = Thermactor Air Divertor
TAB = Thermactor Air Bypass

TAB vents to atmosphere, TAD between the cats and the heads. TAB is the first one after the air pump.
So if the TAB vacuum switch isn't working, is it just dumping the air from the air pump or is it sending it to the diverter and subsequently the heads and/or cats? My gut feeling is that it just dumps it - and it's easy enough to test, but I figured somebody might know off the top of their head.

Thanks
 

·
Junior Charter Member
Joined
·
815 Posts
Remove it from the car and blow through it (really - do this). They are unidirectional and you will assure yourself they are installed correctly and flowing the correct path with no vacuum applied.

I'd guess that the TAB vents to the atmosphere when no vacuum is applied, but am not certain.
 

·
Premium Member
Joined
·
7,237 Posts
Depending on how bad it's misfiring, the computer will think you have a lean mixture (02 present in exhaust stream because of misfire). It then adds fuel to try to trim out the mixture and you get rich/black exhaust. My vote is for a bad pickup in the dizzy. I've got a spare dizzy you can borrow if you want to swap and see if it helps. It's got a ton of miles on it, but it's a known working distributor.
 

·
Senior Member
Joined
·
715 Posts
Discussion Starter · #11 ·
I may take you up on that offer Wade - thanks.

Funny thing is that it if wasn't throwing the 14, I wouldn't even know it had missed? It starts, idles and runs well, but I had observed a sooty #1 plug and then last weekend, when I blipped the throttle before and after some driving, there was some visible black smoke from the exhaust. :(

Last night I check the wiring from the O2s to the ECU and it was fine. The O2's on the car were some used (and newer) ones that I had picked up at some point. Since I still had the old donor ones - and they seemed to work fine on the donor, I went ahead and swapped them out. Both of the ones I removed were equally sooty.

Based on what I read on bad TPS's I took a look at mine since I 'adapted' the '87 TPS to the Explorer TB, and remembered that it wasn't as easy or clean as I had hoped. Anyhow, I tested it in place and it was iffy at best, and when it did work, it's max output was just over 4.2 volts. I have the original Explorer one and it tested fine, so I just need to wire it in. Honestly, I don't remember why I used the old one anyway. :confused: Once I get the TPS wired, I'll reset the computer and try again.

FWIW - I reviewed the instructions for Ryans EGR eliminator and a code 33 is normal when using the device.

Thanks everybody.
 
1 - 11 of 11 Posts
Top