For it is a trouble code...and it's number is 33.

OK, got the car basically running again (new EGR, LTR Plenum gaskets, and a *new* MAF.)

Car runs much better with the exception of an immediate (or almost immediate) code 33 on startup which of course puts the car into limp mode (ick).

A bit more info: This happens without touching the gas or anything, and immeidately after starting. TPS is set to a perfect .54 as measured by the computer itself (adjusted using an auto-x-ray). IAC is sitting at about 50 steps (should be fine).

I also replaced the MAF plug (yes, I got the wires right). All joints soldered and shrunk.

The old MAF was dead due to an intermittent problem (smack it and it worked..smack it again and it didn't). It was the original one from the car (Manufacture date is 1984).

Now, this new MAF is a different style...not the kind we have. It's physically the same on the outside, but the guts are not. This kind uses a bakelite pc board with some circuitry mounted on it and the filement is encased in a plastic wrap and kinda is mounted in a cut out in the board. The whole assembly sits inside the flow chamber. It should flow tons better than the stock one (read: no heat sinks or filement 'thing' sickingin the air flow)....however, I think it's either busted or not compatible with my chip.

Borrowing a BOSCH one from my friend's 87 Formula worked like a champ...no codes with it.

Soooooo....

Has anyone seen this type of MAF before? Problems with it? It appears that this is an adaptation of a different technology, that may work better than the late-70s tech that our systems are based on. However, my concern is that this part MAY NOT BE BROKEN, but may just not give the readings that my TPIS chip is expecting, and throwing the code.

I'm going to send this one back and see if another one works better (it may just be a bad sensor, right out of the box).

Also, I have checked the wiring on the MAF burnoff relay. Contacts look good (covered in dyelectric grease) and I fixed all the insulation problems that happen on those wires where the insulation pulls away (I cut each end off, put heat shrink around each one and re-soldered the ends on and placed them back into the relay plug).

So, I'm stumped....

Any input anyone?

Dan

It's an 86 IROC...
My set up is here:
https://www.thirdgen.org/webmasters/dmartin/stuff.html



[This message has been edited by Dan Martin (edited July 25, 2000).]

 

Dan, is there a brand name on the sensor? I here alot of complaints on non-OEM (non-Bosch) sensors. Names like Napa, Wells, etc... seem to be inferior, and cause problems. Since it runs like a champ with a Bosch sensor, than it sounds like another victory for Delco. I would get a Bosch sensor before trying to chase anything else. I hope this helps you!

------------------
"I used to have a handle on life, but then I used it as a plunger and broke it" -The Wave

ASE Master Tech + L1
Savannah, GA
'87 Trans Am-K&N,Cold air induction, SSM SFC, Flowmaster, 16" GTA rims.
'97 Bonneville SSE
About Me

 

That's the weird thing...no names on the outside.

Was a re-man (hey..who knew?).

Well, I'm going to try the other sensor in it..and if it's a go, I'll fork out the additional dough for the BOSCH one.

Dan

 

That sounds like the Wells SU-145 and there should be a lifetime warranty on that one, depending on where it was purchased. Then again, I don't think you can get a reman SU-145, I think you can only get them new. That particular MAF sensor is said to be much more durable than the Bosch sensor since there is no filament wire to break, but there is circuitry there that could go bad. Try to find out where the MAF was bought then call them up and find out if you can return it.

Also, I think the IAC steps are supposed to be at 30 instead of 50 when at idle, if I remember correctly. I had the same problem though with the code 33 at startup and I know how annoying it can be, believe me. Last September I was having that problem and my mech said if the MAF is ok, (it was new) and the TPS is right, next thing to check is the fuel pressure, which mine was bad. A new fuel pump cured the code 33 until about 2 months ago when my burnoff module (which you don't have) crapped out on me. Good luck to you and keep us posted on what happens.


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Kevin Irving
85 Trans Am WS-6, 305 TPI, custom burned '86 PROM with '87 "165"ECM, Accel Supercoil & 8.8 Wires, MSD 6AL, Aluminum Driveshaft, TB Coolant Bypass, Ported Plenum, Modified MAF, Cyclone Fuel Pump, JET Airfoil

Veiw my car at: http://www.geocities.com/transam85tpi/TransAm.html

[This message has been edited by Kevin Irving (edited July 25, 2000).]

 

I bought the new sensor to replace the original BOSCH one that came with the car (hey, I got like 15 years out of the first one!).

I got the new one at Wrenchhead.com and I'm sure there won't be a return problem.

Anyways, this info is good! Keep it coming!

Dan

 

BTTT...sorry all. Need help on this at all cost.

 

I think you answered your own question:

"Borrowing a BOSCH one from my friend's 87 Formula worked like a champ...no codes with it."

I'd have to guess the one you have is defective. I dont really think its a common problem with the different design.