Im pretty sure its MAF related due to the fact that my MAF doesnt even work.. I smakced it and nothing happened, no sputtering or anything.. The car will only backfire under WOT or after downshifting. Under WOT is what Im concerned about cause its quite alot... I have a check engine light but I dont know how to pull the codes...

 

lol dont drive with wot????

use a paper clip on the furthest right top and botom pins on the connector under the dash

 

If the MAF is good, then it shouldn't sputter when you bang on it.

If you're backfiring, then you are getting additional fuel that's not being burned. It's not obviously misfiring, is it?

When you're WOT the computer defaults to OPEN loop and just dumps in fuel without caring what the O2 sensor is saying. All the car cares about is the MAF reading, RPM, and the fact that TPS is > 4.2V, from there, it's full pulse width, so it's uncommon to have a condition rich enough to cause backfiring at WOT.

Here's what I suggest you check before you replace the MAF.

Check the code, the computer knows there is a problem, you just have to find out what the computer is trying to tell you. Lumper the top two connections, all the way to the right, of the ALDL, then turn the ignition on, without starting the engine. The SES light will blink out the Number "12" 3 times(Blink, Pause, Blink, Blink). That's a normal code meaning that the ECM is not receiving a RPM signal from teh distributor and that the diagnostic system is working correctly. After it has blinked out code 12, it will blink any other codes stored in memory.

My suggestion is to write them down, remove the battery cable for 10 minutes to clear the ECMs memory, then drive the car until the light comes back on, if you can. Then pull the codes again and check out the ones that have been set again.

If the car doesn't drive well enough to go out in it, then just skip the part about checking out the codes that come back after driving it and just start checking the ones that you pull the first time. Clearing the ECM and running the car until the light comes back on is a meathod to find out what codes are actually repeatable and which codes are false. that way you're not chasing false codes down forever.

Once you have the codes, posat them here along with ANY AND ALL modifications or work that has been done to the car just before this problem arose. This will help us to narrow down what information you need to find and fix this problem.

 

Well Ive always heard that if you hit your MAF and it sputters that its good.. but Ill take your advice on it.. Could the timing be off?? I dont have a light to check it but tomorrow in school Im gonan use our auto shops Timing light and check it along with the codes...

 

what you're experiencing could very well be timing. I would definitly check to see if the distributor hold down has loosened as well as check timing.

 

Yeah, only bad MAFs react when you tap on them. Check the timing, as I believe that's where the major problem lies. Be sure to pull the code too, because the MAF might be bad, but just not reacting to the tap test. Sometimes you just can't tell that easily.

 

Well my timing is retarded by 12* How do I adjust it... i tried turning the cap after removing the screws but it wouldnt turn.... Do I have to rotate the entire dizzy??

 

Yeah, you need to move the whole dizzy. Make sure you have another person helping you. First, disconnect the electronic advance; it is a single wire that comes out of the wiring harness on the back firewall. Start the car and let it warm up a little bit. Use a inductive timing light, not the ones that connect between your spark plug and wire. Loosen the bolt at the base of the dizzy, only a little bit. SLOWLY move the dizzy left or right (im not sure) while somebody else is pointing the timing light at the marks. When it is correct; tighten the dizzy back down, turn the car off and reconnect the electronic advance. Your good to go!

 

yessir.. happened to be retarded timing. I had the same problem, but now that my car is showing similar signs about a month later, seems like it may be my harmonic balancer, timing chain, or ?. Glad to hear you've found the problem.

 

Is that bolt clear to remove/loosen without having to take off the intake plenum? Does anybody know wich way I would have to turn the dizzy to advance the timing?

 

yea, you can get to it with everything intact, or else you couldn't change the timing with the engine running.

As for which way to turn it, dunno off hand, but all you got to do is spin it ever so slightly in either direction and you will be able to see the timing mark move one way or the other. Once you figure out which is which, just move it where you need it.

 

Counterclockwise advances timing, Clockwise retards it

 

Im having trouble with this... I cant get to the bolt.. Im gonna have to go get a crows foot or something... Wich wire that comes outta the firewall?? A pic would be great.. Thanks

 

I can get to mine with a 12" extention and a 15mm swivel socket. YOu might be able to sqeeze the extention, a u-joint and a regular socket on the end, I used to do that too.

For a pisture of the EST, take a look at this post, bioth Dale and I have posted pictures of it.

https://www.thirdgen.org/forums/v6/351998-got-running-but-not.html

 

Is 2 degrees advanced a good place to set it at? Or should I put it to 0??

 

Factory spec is 10*, that's a good place to start

 

that could be a different type of MAF or what is known as a VAF. my rx7 is setup like that. where instead of a hotwire setup they have a flapper door. the more air that enters your motor the more that door opens up, so when you bang on it you can move the flapper around. your setup though I'm thinking should be a hot wire setup. it works by making a wire going through the middle of the MAF hot. the maf tries to keep the wire the same temp all the time. the more air that flows through the maf will cool it off more and the maf will pass more current to keep the wire the same temp and the computer will monitor that. smacking the maf isn't going to affect the temp in the maf or anything else unlike the flapper door style maf.

only way a hotwire MAF is going to react is if something is wrong with the MAF due to a loose wire, connection or something like that.

 

Well the Timing has been set to 10*.. Runs smoother but under WOT it still has the same problem... Could it be a miss thats actually occuring?? If so should I just do a tune-up and see if that solves the problem?

 

Yes, check your plugs and wires.

 

Could running mid grade have fouled my plugs?? i was using 89 octane cause it was helping out before i adjusted my timing...

 

Theres also a slight hesitation....

 

Well I replaced the plugs and found these....