C4 General Discussion General C4 Corvette Discussion not covered in Tech

1987 /Code 36,33.

Thread Tools
 
Search this Thread
 
Old Oct 6, 2020 | 06:04 PM
  #1  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default 1987 /Code 36,33.

again. Does this model require the burn off wire? I had ordered a maf sensor, when I got it, there wasn't a wire in it. Installed anyway still got 33, and 36. Any advice would be appreciated. Any documents to trouble shoot would be great. Thanks in advance. I do not like the fact that I don't know how .
Reply
Old Oct 6, 2020 | 10:58 PM
  #2  
jv9999's Avatar
jv9999
Melting Slicks
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jan 2014
Posts: 2,185
Likes: 381
From: Lunenburg MA
Default

The '87 does have a burn-off wire and relay. It sounds like you got the wrong part. Who makes it?
Reply
Old Oct 7, 2020 | 07:08 AM
  #3  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default Mass air

Seems China Makes it. Part # REPC316708. Ordered from carparts.com. I called them and found out that none they sell has the burn off wire. I'm returning it. It was not expensive. So I figured I would try it to see if it would clear the code . Car still runs ok. Dang service light drives me nuts. 33 code just started. I'm thinking that the MAF sensor has something to do with that to. I have a Haynes book , but that doesn't help much.
Reply
Old Oct 7, 2020 | 07:24 AM
  #4  
vader86's Avatar
vader86
Team Owner
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2001
Posts: 62,142
Likes: 1,729
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Default

Haynes is not that useful, nor is Chiltons. Maybe some pictures or one or two things.

You need the Helm Factory manual. Best money you can spend.

It has the full procedure to troubleshoot the MAF codes.
Reply
Old Oct 7, 2020 | 08:06 AM
  #5  
kael's Avatar
kael
Drifting
Supporting Member
10 Year Member
 
Joined: Nov 2015
Posts: 1,709
Likes: 329
Finalist 2020 C4 of the Year - Unmodified
Default

Search around here, plenty of threads regarding the dreaded code 36, burn off circuit failure.

My solution (eventually) was to purchase a replacement MAF without a burn off circuit, for a reasonable price I might add. Then had the MEMCAL changed by a tuner to disable the code 36 check. Upgraded the old EEPROM to flash at the same time.
She runs great this way.

Tidbit: If code 36 is cleared by disconnecting battery, it will NOT trigger until engine has been run to normal operating temperature, turned off for five minutes and engine restarted. Clearing the code and not seeing on first ignition on does NOT mean it's fixed.

Last edited by kael; Oct 7, 2020 at 08:07 AM.
Reply
Old Oct 7, 2020 | 08:32 AM
  #6  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default

Yes. Sounds like a good idea.. how ? I have nothing here to do it
Reply
Old Oct 7, 2020 | 09:28 AM
  #7  
KyleF's Avatar
KyleF
Drifting
Liked
Loved
Community Favorite
 
Joined: Jun 2018
Posts: 1,678
Likes: 229
From: Michigan
Default

Originally Posted by kael
Search around here, plenty of threads regarding the dreaded code 36, burn off circuit failure.

My solution (eventually) was to purchase a replacement MAF without a burn off circuit, for a reasonable price I might add. Then had the MEMCAL changed by a tuner to disable the code 36 check. Upgraded the old EEPROM to flash at the same time.
She runs great this way.

Tidbit: If code 36 is cleared by disconnecting battery, it will NOT trigger until engine has been run to normal operating temperature, turned off for five minutes and engine restarted. Clearing the code and not seeing on first ignition on does NOT mean it's fixed.
This is about right. I have dealt with a code 36 on many cars. The new hto film units are supposed to have a spoof circuit to send pass the voltage from the burnoff relay voltage back to the ECM. I had one of these, and it didn't always work right. After 3 cars... I am over the old MAF system and converted to SD. If you have a hot film style, turning off CODE 36 is no big deal. Your Code 33 is probably a sign of a real issue. The engine is getting more air than it wants based off the MAF reading. Vacuum leak or and intake tube leak upstream of the MAF.

However, both happening together would lead me to inspect the wiring between the ECM and MAF very closely. If you have an FSM, you could see the wire colors and pin# to be able to check for continuity between the ECM plugs and the plug for the MAF.
Reply
Old Oct 7, 2020 | 10:22 AM
  #8  
jv9999's Avatar
jv9999
Melting Slicks
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jan 2014
Posts: 2,185
Likes: 381
From: Lunenburg MA
Default

You can download the real SM here: https://www.dropbox.com/s/wmizdbj1cj...20SM_.pdf?dl=0
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-1

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-2

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-3

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-4

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-5

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-6

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-7

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-8

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-9

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
Old Oct 7, 2020 | 06:26 PM
  #9  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default the

Going to get one from O'Reilly I guess tomorrow. The one in the car i know is broke. Seem that the tab? Inside broke off . It fell out in my hand I don't know how delicate the interior stuff is. Anyway, we shall see. Thanks for the book. Going to do some reading this evening.
Reply
Old Oct 8, 2020 | 12:53 AM
  #10  
65Z01's Avatar
65Z01
Team Owner
20 Year Member
 
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Default

If you unhook the front of the MAF from the intake you can use a mirror to watch the sensor wire inside the unit when you turn off the ignition to see if it glows.
Reply
Old Oct 8, 2020 | 05:46 AM
  #11  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default

The wire did glow.....before. Just for grins , I'm going to recheck it again today. Still need to replace it. From what I'm reading, the outboard relay on the firewall is the one that feeds it. I will be letting you know . It seems that a good troubleshooting description here would help folks with limited access to books. I checked YouTube and could find nothing on a step by step procedure. Seems to it would be good idea for these pesky ones
Reply
Old Oct 8, 2020 | 04:38 PM
  #12  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default

Follow Up. Don"t buy a duralast DL-6014. One store had it that would fit in the area. When I peeked inside of it , There looked like a wire in it. Nope. Was not. Taking it back tomorrow. Also shipping back the one from carparts to. I put the old old back on . Bosch Brand. wire on it still glows. so i dunno . may i should be working code 33 first. Back to reading.
Reply
Old Oct 27, 2020 | 03:35 PM
  #13  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default

Another update . I just replaced both relays on the firewall. Started the car, 4 seconds later, service light back on. Went for a ride about forty minutes before shutting if off . I had to do some stop and go shopping with turning the engine off and restarting. Got home and then checked for codes. I got 33 code again but no 36 this time . seems 36 code was a bad relay. One down, 1 to go! I'm still looking for ideas ? The Bosch MAF sensor had a part that looks like a tail Rudder? on a plane. It had fell of when I touched it , just a tiny bit sticking up now. would that give a code on startup? Car still runs really well tho. ..I'm always looking for that magic answer. I would like to be sure before buying 1.
Reply
Old Oct 27, 2020 | 05:59 PM
  #14  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default

Question I forgot to ask . On Rock Auto, The Walker Mass Air flow sensor states that it does not have the burn off circuit. Does that mean that the rest do? Would any work for me?
Reply
Old Oct 30, 2020 | 04:28 PM
  #15  
olrusty's Avatar
olrusty
Thread Starter
Advanced
 
Joined: Sep 2020
Posts: 61
Likes: 7
From: Spotsylvania Va.
Default

Last update on this from me. No Codes. Went to Zip Corvette (close to me, 50 miles) And picked up their instock Maf Sensor. Installed it .. fired it up, waited 4 seconds,ten seconds. engine smoothed out and no codes. I also bought a headlight switch **** . Wrong one. That was a really good excuse to take it back ..had to check for the 36 code. down and back.. no codes.. still need the headlight switch ****. Thanks for all the input and suggestions.
Reply

Get notified of new replies

To 1987 /Code 36,33.





All times are GMT -4. The time now is 04:27 AM.

story-0
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-1
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-2
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-3
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-4
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-5
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-6
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-7
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-8
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-9
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE