Code 36 MAF unit. have ?'s step inside!

[Mad-Mic]

ok i finally got the car scanned as my friend finally had time to stop over with his scanner. after changing the O2 sensor the car felt like it was fixed and was pulling hard down low and spinning 275/40/17" BFG DR's over at will thru 2nd gear. (Ask Rich R about the ride i took him in ) well the car eventually went back to it's sluggish self on the low end again.

Code 36 came up which is the MAF and or Relays. it's dark out now and i haven't checked the MAF wire yet but will tomorrow when i find some time. my question is if it's the relays where are they located at and where can i buy them at? if it's the MAF itself i'll see if Rich will let me borrow his old one for a few weeks until i get some extra fundage in the pockets and will spring for a new aftermarket one that is ported. which MAF do i go with?

at idle upon startup the car is pulling over 10 grams per second past the MAF itself. stock setting range is 4-8 grams per second. is there anyway to check the relays? if so how and where are they located?

thanks for the help!

Mic

 

[Vettefan87]

Im assuming you mean the MAF power and burnoff relays? If that is so they are right behind the battery on the firewall, it is not hard to change them, I think it took me 15-20 mins if that. I know that they have them in Mid America, I think you get a little break if you buy them both, something like 14 or 15 bucks sticks in my mind. I would definetly start with the relays since they are very cheap compared to a MAF sensor.

I am unsure how to check them. My guess would be to maybe find someone with a good MAF and swap it out and see if it runs better. If not then you know it is the relays, I don't think driving the car with the relays bad will damage the sensor, I did it for about 3 months with no problem. Good luck

 

[G Winter]

Unless a relay is burned out it is hard to check them. over time the contacts can get burned and not always make good contact. As cheap as they are,considering the age if there is any question I would replace them.

 

[vetteboy86]

I had a bad relay, that threw a code 36 but it didn't make the car doggish. I replaced the relays and no code. It does have a better cold start now. You can check the relays, I will have to look at them. I threw the old ones away, not anticipating this question obviously.


Craig

 

[redc4corvette]

Mike I don't know how different the 86 is from your 87 but mine threw a 34 code and the short of it ,after test it threw a code 33 and that told me it was the MAF.The 34 if it threw it again ,then the book says the ECM would be bad.

Mid america has a maf that is adjustable for $329.00.

I paid $170.00 for a reman.

Works fine now,when I hit the nitrous it blew out the screen in the front and cracked the plastic. I did not have the clamp tight.
Another one of those destist oopsis.:ugh

 

[Mad-Mic]

thanks fella's! when i i get some time in the daylight i'll check the MAF and borrow Rich's and see what happens but i'm leaning towards the relays since one day it runs fine and then the next 5 days its doggish again.

wish me luck!

Mic

 

[Vettefan87]

Yea mine would do that too, one day it would run pretty good, then the next it would be hard to keep idling at stop lights and hesitate when taking off..

 

[nyernga]

You might check the connections to the relays as well. I have found in my work that relays generally either fail open or fail closed and do not act intermittently. A loose wire going to the relay however would cause that condition.


Len

ps: the manifold is doing great...........

 

[jmccloud]

Intermittent MAF

My son had intermittent performance similar to yours so I bought him a MAF for his birthday. Turned out it was the CONNECTOR to the MAF. One of the leads didn't reliably connect to the prong in the connector on the harness side. We found it by measuring continuity via straight pin through the lead insullation (into the conductor) to the prongs. The initial clue was that flexing the wires to/from the connector during warm-up produced sporadic cure.
His car was also very difficult to get started.
Hope this helps

 

[RonJ]

With the engine idling, try tapping the MAF sensor with the handle of a 6" screwdriver. I don't mean belt it with a 3 pound hammer, just tap it lightly.

If the engine stumbles with every tap, it's a sure thing it's euchered.

Mind you, if it doesn't stumble, that's not to say it's good ...

Ron ...

 

[Mad-Mic]

i just got off the phone with NAPA since they are the ones redc4corvette suggested to me over on CF in someone elses thread but when i called them they only know of 1 relay for the MAF and that is the MAF burn off relay. what other relay do i need?

thanks!
Mic

 

[Vettefan87]

the power relay, if NAPA doesnt have it I know Mid America does http://www.madvet.com/shop?frame=3.3808 both for 17.99. and there stuff have always ships fast. Hope this helps

 

[jrbartholomew]

mic go to chevy dealer and buy 2 relays #14089936 the are 87 only. i also had to clean my throttle body to get the codes to stop.hope this helps.

jeff

 

[Mad-Mic]

mic go to chevy dealer and buy 2 relays #14089936 the are 87 only. i also had to clean my throttle body to get the codes to stop.hope this helps.

jeff

Jeff thanks for the info. the NAPA sales guy said he couldn't find another relay for it but then again i didn't know the name. the one from NAPA is 12 bucks.

i know about the relay on the firewall near the battery but where is the other one at?

thanks for the info guys!

 

[redc4corvette]

Mike the burnoff is echlin #ech ar 227 that is the burn off,
the other is a/c iac fan ech ar 226.
burn at napa 14.49
a/c iac 7.79
Deal$22.26
List with no deal 30.77

 

[Heavy Duty]

Guys i have sore of the same problem. First off..Mad-Mic if you don't mind and sorry for hijacking your thread. I was going to open a different thread but this one seems to be heading down the right path.

Now..Mine has went through 3 MAFs in the past 1 1/2 year. The last one just recently. I dropped the car off to have it painted this past November. The guy called me last week and said that the car was running like crap. No codes. Unplug the MAF and it idles fine. but runs very rough when the MAF is plugged in and very hard to start cold. So we think it is the MAF again. The last time it went, it took the ECM out as well. When I bought the car the guy had to have a new MAF put on the car because mice had chewed through the ECM wires and caused the ECM to short and in so doing , the MAF as well. I bought the car and shortly after I bought the car it started running like crap. Had a buddy of mine look at it and yep...MAF and ECM both fried. We didn't replace any relays. But he did go under the dash and re-spliced the wires.

Now with this lastest I am thinking that either the wiring is hosed and causing the shorts, voltage spikes, or maybe the Relays are bad and they are causing the MAFs to go bad after 6-8 months in the car. I think that the MAFs don't cause a lot of trouble. But again i just may have a basket case on my hands. Any suggestions.

Thanks and Mad-Mic thanks for letting me ask.

H.D.

 

[jrbartholomew]

mic mine were behind the battery. power relay and burn off relay.both same #
if i remember about 10$ a piece.
jeff

 

[G Winter]

mic mine were behind the battery. power relay and burn off relay.both same #
if i remember about 10$ a piece.
jeff

Are they the same as the standard automotive relay used all over by GM ?

 

[Vettefan87]

Jeff thanks for the info. the NAPA sales guy said he couldn't find another relay for it but then again i didn't know the name. the one from NAPA is 12 bucks.

i know about the relay on the firewall near the battery but where is the other one at?

thanks for the info guys!

They should both be sitting right next to each other. That is the way they were on mine.l

 

[redc4corvette]

HI JACK A THREAD!! Even the part numbers for excel relay's from NAPA.
Mike and I just got threw replacing that junk.
Everything you need to know is in this thread.





The factory manuel always recomend the relays be replaced when a code 36 is thrown.
It's is a service item that chevy recomends.
If you are cutting and splicing wires it builds resistance and could, but not likely put a load on the ECM.
You should also know the 1986 corvette has the worst wiring of all the vetts.
Something with the coating not to mention putting the wires next to the EGR tube which gets about 900 degrees,where the main harness goes through the fire wall.
NICE MOVE CHEVROLET!!

If anyone needs the factory break down sheet for code 36 another member sent it to me ,let me know.