Can't get rid of it, any ideas?
I know the MAF is working but it reads .25 at idle instead of .50 and it just stalls and resets code 34. The MAF is new, engine is new, the diacom shows the MAF voltage increase when the throttle is opened. Any help would be appreciated.

 

Replace the MAF power relay, unplug the battery for a minute, and see if the code comes back.

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Greg Westphal
'87 IROC 305TPI/A4

 

is your tps adjusted properly to specs??

 

Yes, everything is adjusted properly.
I changed out the relays and the 34 went away (after I disconnected the battery that is)but as soon as I tried to let it idle it came back. The Diacom showed the MAF wasn't working, but after I switched the relays and checked the connections again, it showed it was working again. It reads higher voltage when reving the engine but a low voltage signal when it trys to idle.

 

Vacuum leak is causing 'false air' to enter drawing less air through the maf, therefore a low voltage and a code 34

 

Either a vacuum leak in the induction system or check your MAF sensor connector and see if it is making a good electrical connection.... It also might be a good Idea to check if the MAF is lined up properly...

 

Thanks Guys
I'll check for a vacuum leak.

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Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies

 

I had that damn code 34 for 5 months. Possible causes are bad burnoff relay, bad MAF sensor, leak in intake tract, or bad ECM.
I changed my relays, it went away and came back. Turned out I hit a nasty bump and it broke one of the tiny wires in the MAF.
Just check everything thoroughly.

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1980 Camaro, '88 Police 350 engine, Headers, full exhaust, completely redone, my baby!
1988 Iroc-Z L98, MSD 6a, Accel coil, K+N's, Airfoil, Coolant Bypass, Flowmaster, Gears, Late model Bose, I like the 80 better

 

Don,

In addition to the above advice, check the PCV system to make sure it is getting its air supply from the throttle body connector. Also make sure the trim cover plate on top of the TB is tight and not leaking (the cover that reads "Tuned Port Injection".

Make sure that the oil filler cap is tight and sealed, and NEVER use a breather type filler cap on an EFI engine.

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Later,
Vader
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"Fear is how I fall, Confusing what is real..."
Adobe Acrobat Reader

 

Ok, here goes: I had an intake leak (#2-4 tube tiny leak, talk about touchy) fixed that, no more code 34. Next problem when it idles at about 800 and up it shows o2 readings of less than 100 Mv, bringing it up to 2000 rpm's it will go up and down 400 to 800 Mv and all around there. It shows dead lean and runs like it until it reaches 2000 rpm's then it runs great.
Where do I look to eleviate this problem?
(sheech, give me S/D any day)

------------------
Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies

 

If your motor isn't stock with the tpi (diff cam), a custom PROM, more fuel pressure or bigger injectors may help.

Disconnecting the vacuum reference and plugging it will raise the pressure on the lower load range (low rpm and light cruise/high vacuum conditions), you could try this and it might help but isn't the correct way to go about this...but it's better than running lean. A scan tool would really help you out, maybe a sensor is acting up. I never saw this problem before.

 

I'm using Diacom.

------------------
Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies

 

How did you find the leak on the intake. I am having the same problem with my son's car but I get no codes. I have replaced everything!!! Sensor, both relays the connector to the sensor and even the ECM. The ses light comes on when it wants. Sometimes it will go 2 or thre days without a problem. Then on it comes and the car runs like crap but no codes only 12(all clear).

 

Sparingly spray starting fluid on all the possible places that may have a vacuum leak. If there is a leak, the idle should pick up due to the ether the car is now burning.
You also want to do this after the car is cold so you don't inadvertantly set it on fire spraying it on the exhaust manifolds.

Disclaimer: There is a significant risk of fire from using this method. I take no responsibility if you blow up either yourself or your car.

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http://www.havemann.com/lee/firebird.html
1989 Firebird Formula, WS6 Package
ZZ4 Crate engine, Accel 24 pound injectors, Accel Superram intake, Accel Large tube runners
SLP 58 mm throttlebody, Edelbrock TES headers, SLP 3" SS exhaust, Random Tech 3" hi flow cat
700R4 trans w/ vette 2/4 shift servo, worked valve body, kevlar band, 2200 rpm stall converter
Borg Warner 9 bolt rear (full poly mounts) Hotchiss panhard rod, Lakewood LCA's, Spohn subframe connectors, self modified chip.

 

Looks like my problem was a bad IAC valve.
It idles now just have to go back and re- adjust everything
I guess I missed it, the counts were up around 140, now at 80.
Thanks to everyone for responding with help.
Don>>>

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Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies

 

You could use an unlit propane torch. Little safer than ether!

 

Usually any type of vacuum leak shows up as a code 44. It would be pretty unusual to show up as code 34 without also tripping a 44. I have found that code 33 & 34 are usually solved by either new MAF or Burnoff and Power relays.

Also if any of you are dealing with a 86 model it is probable that you have the "bugged" PROM that Vader pointed out to me once. It will set false codes.

If you ever suspect a vacuum leak start FIRST with checking the intake bolts for tightness BEFORE you waste 10 months and a few hundred bucks like ME....

 

Don, are you using the 88 code? Switch it to 89. Tell Kevin to do it.

 

Switch it on what, the Diacom?

 

No, he's refering to the chip, changing it from the 88 style to the 89 ARAP style.

This is on a customer's car, and he doesnt want to switch to 89 code right now, lack of money.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.23 @ 107.62 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

Oh I see...