YAY me.. she runs now... runs real good until you hook up the mass air flow sensor, and then she dont run at all.. start it, she'll rev up, as soon as the rpms come down she dies.. what gives, its a new MAF, the second one actually, i got one out of a junk yard that did the same thing, so i figured it was bad, turns out i was wrong... ive checked for leaks to the intake and came up with nothing.. any body got any ideas???

thanks

 

so from what ive read so far i can assume that the problem may be the relay or relays, the hot and the burnoff, both haveing the same part #, but are they just one relay and whats the part #??

 

Hey man. Easy way to test the relay. Simply take you fuel pump relay and put it where your MAF relay is. They are the same relays This will tell you if it is the relay

 

for any body looking for the mass air flow sensor relay.. on my 89' firebird it was on the other side of the air filter houseing, on the radiator bracket, the part # is 8309 and under that is 14089936 camaro350man if i take the fule pump relay out how is the car going to run???

 

Fuel pump relay is not required to run the engine. There's an oil pressure backup switch that activates the fuel pump when oil pressure is present.. oil pressure means motor is spinning, so...

You'll just have to spend an extra few seconds cranking to build up the oil pressure to trigger the switch and click the fuel pump on.

 

The few times I bought a MAF I was told by the store that the battery had to be unhook when unplugging and hooking them up. If not it can blow and they will not honor the warranty.

Some say it don't matter but the few Min's of extra work never seamed to bother me.

better safe then sorry.

 

ok so ive discovered that the plastic air box thing that sits ontop of the raidiator was broken at the seams, i glued that back together and made it air tight again, and dissconnected the batt for a while to clear out the trouble codes, got every thing back together and after adjusting the TPS just a hair she'll start and stay running for a bit, but she idles rough and after a bit when warm will start cutting off on me... im a bit brain fried, the timeing has been adjusted and ive done every thing i can think of..
if any body has any suggetsions about the rough idle and the cutting off i am more than happy to listen..

 

I don't know about your 89 firebird, but on my 89 camaro. The relay at the radiator is for my fans. The relay for my MAF sensor power relay & MAF burn-off relay are on the driver side firewall and are different part numbers and designs than the fuel pump relay. The fan relay is the same part number as the MAF sensor and the MAF burn-off relay. Your problem could also be the MAF sensor or somewhere in the wiring, probably at the connector.

 

Trickster, he has a 2.8, not a 5.7.. the relays are in two different locations and the two engines use two different MAF sensors.

If you are afraid of killing the MAF without the battery disconnected, remove the relay. That cuts power to the MAF so you don't have to worry about it. Check your connections at the relay and sensor to make sure you have good wiring and connectors. Also check for vacuum leaks, etc. Pull your plugs and look at them for signs of trouble, such as being sooty black, noting that the engine is running too rich, etc... Yada, yada, yada..

Also, when replacing the MAF, look at the frequency film inside while having a light over your shoulder so the light reflects off of the film. If the film does not appear to be perfectly flat, go and get a new one...

One last thing, have you checked and/or cleaned the idle air control motor? The ECM uses a preset position for idle, and if too much carbon and junk gets in the passageways, it can gum up the works...

 

My bad, Maverick H1L.

I missed the 2.8L in his engine size Sorry!!!!!!!!!!

 

Hey, no biggie. **It happens...

 

You are aware you're posting on the V6 board, right?

 

Notice the !!!!!!!!!!!!!

 

the one and only thing that i havent really looked at it the IAC and i should have, it did blow apart one time when i for got to reinstall it and started the car, so either i need to readjust it or get a new one and make sure its set right, ill keep every one posted....

 

Not the IAC, it was off of course, but when i adjusted it the car seemed to run worse, im about give out on this thing, i really dont know what else to do..

 

Ahem....

 

sorry maverick..

i replaced the plugs something like 2 weeks ago, since then the car has only been run a hand full of times.. but it does seem to me that she is running a bit rich (i can smell gas when she is running) the thing is when i dont have the maf connected it starts and idles just fine, and doesnt seem to run rich.. my thinking is that either the new MAF is a bad one, the connector is hosed.. Or
could the timeing being too retarded cause such an idle problem with the maf connected, ya know insted of it working off of preset tables its actually measureing the air and not being able to burn off the gas do to poor timeing??

 

Only one way to find out...
With the MAF, it may be either the wiring, relay, ECM, or the sensor itself, listed in range from least expensive to highest prise in left to right. Yes, the ECM costs less than the MAF, depending on where it comes from.

 

You are not allowed to give up on teh car unless you have at least 1 engine fire & kill the harness. The ECM is prrogrammed to substitute it's own MAF values when the MAF is disconected. I'm still puzzled by the gas smel. When I was running 58octane out the tailpipes, it hardly smelled like gas.

 

Hey, I just thought of something, not sure but thought I should find out:
Is it possible he has a corrupted PROM or CALPAK? I remember reading something about some year getting bad chips...
Seems to me that the ECM is in trouble here. Too much gas and too little air or something....

 

It could also be his timing being at least 20 degrees retarded with the distribtuor at max adjustment, which is what he explained it was today.. I don't know what he was using as a timing mark to say it was set at 10 btdc before... plus his TPS is still out of whack... we'll see where things stand in a week after he adjusts the distributor and gets the TPS set right. Gotta fix everything that's known to be wrong before blaming the MAF.

 

im going to disconnect the MAF and make sure every thing is adjusted right, and also check out the harmonic balencer just to make sure its not shifted at all, while im at it i may just get a new timeing chain just so i know for sure its all in good repair.. its gonna be about a week before i can get to it again though, i work 3hrs from home, but i may be in trouble i found an 86' TA that seems like it could be a good bit of fun, but it too needs work..
nothing like haveing TWO project cars...

maverick, ive checked the relay and the voltage at the wireing for the relay and then sensor it self, im gonna replace the connector just to see if thats the problem, the sensor it self souldnt be shot yet, but ill have it replaced just to make sure on that too.. and uhhh whats an ECM, the computer itself???

 

ECM= Electronic (Engine) Control Module, aka PCM (powertrain module), aka ECU (elec control unit), aka "brain box" or "brain", and finally, aka computer.

 

well it took long enough but she runs, and she runs with the MAF hooked up.. i had to get a new one, insted of a rebuilt one but it was worth it... the only thing left to do is a little fine tuneing for the idle (gonna take it to a shop to have the tps replaced and adjusted) and she'll be back to her old self again.. i hope...

 

like the thread saies, its alwase something...
I started the car today and the idle is very rough bounceing between stalling and 1k, put it in gear and she just cuts out compleatly. i have noticed that the exaust now has a very muffled sound insted of her normal throaty sound, mabie shes not breathing right and thatll fix it (replaceing the exaust that is)
or theres something elese wrong, cause after a while that muffled sound whent away and she whent back to sounding normal but still the idle problem and the cutting off..


EDIT: need to mention that it only idles rough and stalls out/cuts off in gear after it has warmed up to normal operating temp. also ive been informed that with it poping and back fireing that it is very possible that its jumped timeing badly, and now with every thing (MAF) working the way it should the timeing is screaming for my attention... i didnt have this problem until after i put in a properly working MAF.... :werd: