MAF relays on an 85

[mdsbch]

I got my 85 Vette about a month ago, and it ran great for a few days, then it started cutting out intermittently (mostly when giving it gas at idle). It idles Ok until you push the gas pedal. It is giving codes 32 and 33. After researching several articles in this web site (http://corvetteactioncenter.com), I’ve decided to replace the two MAF relays. I called AutoZone and Murrays Auto parts, and both of them said they didn’t have any listing of the part. One of them suggested using the fuel pump relay as a substitute. Can this be done or are they different relays? If they are different, does anyone know what the part number would be and where I can get these relays? Also, after studying my Chiltons Repair manual, fig 70 on page 4-24 shows the Vin 8 engine electrical diagram for the MAF (I am assuming this is the one my 85 has) and it shows both the MAF Sensor Burn-off relay and the MAF Power relay. However, when I look at fig 91 on page 4-31, it doesn’t show the location of these relays for the 85 Vette. I looked behind the battery where it seems they are on later models, but there are none on my 85. I did find two relays in the general area, one in front of the battery on the inside of the wheel well and the other between the battery and the engine on the fire wall. Are these the MAF relays? Thanks for any help with locating these relays both in the Vette and at an Auto store.



Mike

 

[Ken]

First of all Mike, Code 32, according to my book, is a trouble code for the EGR system.

As for the relays for the MAF sensor, again, my '87 book has them both located behind the battery/cruise control; the one on the fenderwell ahead of the battery has another function, but I cannot at this time remember exactly what it's function is. :L

 

[vader86]

85 does NOT have relays behind the battery, it doesnt even have the relays anywhere.

Its a unique year.

The only thing other than the MAF sensor that should cause the code is the Burnoff Module, which is buried behind the passenger side dash. Its rather expensive since its a unique piece to 85 only.

 

[limomanb]

MAF relays fopr 86' advice.

Having the same type of problem with my 86'....I'm going to change out the relays as well....does anyone have the NAPA and/or Autozone part numbers?

Mine doesn't cut completely out...but sometimes bogs down when accelerating from idle, then it "catches up". Immediately after this...the SES light comes on.
It's a mixed bag..one time I'll start it....take the car out and it's perfect.....the next time..I get the bog down and SES light.
It's like a box of chocolates...I never what I'm going to get. Something is not right though.

 

[mdsbch]

Thanks Vader86. I was beginning to wonder if they didn't use the relays on the 85's. I did however, put new plugs in and check all the plug wire resistances and it is running much better now. Thanks again.

 

[FRANKDIAZ]

will the maf burn off relay affect my fuel because my whole entire passenger side injectors are not working

 

[Curious George]

will the maf burn off relay affect my fuel because my whole entire passenger side injectors are not working

MAF burn-off relay and injector circuits are isolated, so the problem is not related. If your passenger side bank is not firing you have a shorted injector on that bank, possible wiring issue or a bad ECM.

CG

 

[93Rubie]

I do not know for sure but my rule of thumb is "if in doubt take it out."
Otherwords, if you suspect a bad MAF or anyother sensor for that matter. Disconnect that sensor (KEY OFF!!!). The computer should subsitute a defualt setting to allow the engine to run. Did this last week on a Mercury Mariner. Guy towed it in would start and then just die. Had fuel pressure, but both Front 02's had lean codes, which got my attention. For grins and giggles I disconnected the MAF. Started and ran fine. Pulled the air filter out. FOUND the problem, it was very black and very old for a 40K car, original in fact. Some of the filter had came off and got on the hot wire of the MAF, causing all kinds of mayham. Cleaned it off and the car ran like new. Goes to show that maintenance is important and if neglected can cause stupid problems that otherwise would never happen.