[MAF] relay connections
Thread Starter
Pro
Joined: Jan 2001
Posts: 681
Likes: 2
From: Newton (Wichita Area) Kansas
[MAF] relay connections
I've been having lots of Code 33 problems and so far haven't been able to find the source of the problem. I inspected the wiring harness connections just now and noticed that the harness connectors for the 2 MAF relays are in pretty sad shape. Two or three of the wires on each connector have lost their insulation in the area closest to the connector. It doesn't look like they could be shorting out on anything but it might be indicative of other problems with the connector.
The pins move in and out quite a bit but maybe this is by design. Can somebody verify this for me?
Both relays and the MAF are new but I'm still getting intermittent Code 33's. The car runs decently, sometimes with a surging idle, and then after about a block or so of driving I usually get a Code 33 and it runs like it wants to die. If I turn the key off and wait a few minutes the Service Engine light goes away and the car drives just like it did before the Code 33. To me this seems like an issue with the MAF system rather than a vacuum leak.
Anybody else ever encounter something like this?
The pins move in and out quite a bit but maybe this is by design. Can somebody verify this for me?
Both relays and the MAF are new but I'm still getting intermittent Code 33's. The car runs decently, sometimes with a surging idle, and then after about a block or so of driving I usually get a Code 33 and it runs like it wants to die. If I turn the key off and wait a few minutes the Service Engine light goes away and the car drives just like it did before the Code 33. To me this seems like an issue with the MAF system rather than a vacuum leak.
Anybody else ever encounter something like this?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: [MAF] relay connections (jmr302)
See if you can find someone with a Bosch MAF.
I had similar symptoms, without the codes, and swapped in the MAF from my IROC to verify the problem cause.
I had similar symptoms, without the codes, and swapped in the MAF from my IROC to verify the problem cause.
Instructor
Joined: May 2002
Posts: 150
Likes: 0
From: Richardson Tx
Re: [MAF] relay connections (jmr302)
I am currently experiencing the same problem your having. I have replaced 2 MAF sensors and the "power on" relay for the MAF. I have not replaced the relay that controls the burn. (I don't know anyone in my area that has a BOSH MAF that I can use as a test.) The connections at the relays were tight and clean with no loose pins or corrosion. I have traced the wires from the MAF to the firewall to check for breaks and tears in the insulation and the connectors are clean. There are no leaks between the MAF and the throttle body. The throttlebody and intake plenum have been removed and cleaned and checked for leaks. IAC and TPS have been replaced as well as a complete tuneup. I have even pulled and cleaned the EGR valve. I started having this problem about a month ago. The service engine light comes on when I am doing 35 or 75 and it always happens when I just barely give it gas to maintain speed. Mine does the same as yours on a restart. The code is triggered if the engine is cold or warmed up to operating temp. I am at a complete loss as to what is causing this and hope that someone here can help. I am beginning to suspect a bad ECM.
Race Director
Joined: Sep 2000
Posts: 12,182
Likes: 1
From: Partying with the Cowboys cheerleaders in Mt. Olive, New Jersey
Re: [MAF] relay connections (jmr302)
Son of a b*tch, you are describing exactly what I've been experiencing with my '86. With me, it's usually during hard rain, search for my other post within the past couple days. Both relays are new Delco units, and the MAF is a rebuilt Bosch. I'm hoping what happened to me is moisture related issue. I have taped a clear plastic sandwich bag over both relays and the power junction until I can find time to insulate the area and clean/re-route the black rubber drain tube. :mad
Burning Brakes
Joined: Apr 2002
Posts: 755
Likes: 0
From: Patterson CA
Re: [MAF] relay connections (CoolVette86)
Same problem here :crazy: . I replaced both relays about 2 weeks ago, it was happening about every other day just as I need power to pass a big rig or some slowboat on the highway, but it has also happened in town leaving a stop. The problem hasn't been back since I replaced the relays, but the problem is so intermittent it's really hard to tell if it's corrected. Mine has only happened when the weather is really warm, 80F+, it never has happened when it's cool out. :confused:
Thread Starter
Pro
Joined: Jan 2001
Posts: 681
Likes: 2
From: Newton (Wichita Area) Kansas
Re: [MAF] relay connections (CoolVette86)
Looks like we need to form some sort of support group!
I'm still not entirely sure I don't have a vacuum leak somewhere. There's so many places for leaks to occur on these TPI intakes. Makes me yearn for a speed-density LT1 car or something.
When I put my 383 in I sent the MAF to TPIS to be ported. Thinking that MAF was possibly bad I bought a brand new MAF from TPIS that they also ported. This was after replacing both relays with new Delco pieces.
Near as I can tell all the pins in the relay connectors have continuity with their wires but I'm going to experiment with that. I gotta find some jumper wires and then I'll test my theory out.
I'm still not entirely sure I don't have a vacuum leak somewhere. There's so many places for leaks to occur on these TPI intakes. Makes me yearn for a speed-density LT1 car or something.
When I put my 383 in I sent the MAF to TPIS to be ported. Thinking that MAF was possibly bad I bought a brand new MAF from TPIS that they also ported. This was after replacing both relays with new Delco pieces.
Near as I can tell all the pins in the relay connectors have continuity with their wires but I'm going to experiment with that. I gotta find some jumper wires and then I'll test my theory out.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: [MAF] relay connections (jmr302)
If you don't have a scan tool, MAD has a test harness for the MAF for about $16.
If you suspect air leaks you could check manifold vacuum.
If you suspect air leaks you could check manifold vacuum.
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Instructor
Joined: May 2002
Posts: 150
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From: Richardson Tx
Re: [MAF] relay connections (VetBoy89)
Mine did not start until the weather got into the 80's and it happens if it's raining or sunny. I will replace the other relay tonight and see if the problem reappears in the morning.
