Is this a bad MAF?

[blackbuick87]

Over the last couple of weeks, at the same time I have been trying to tune my new alky system, the car has been getting progressively worse. I have been blaming the alky system, thinking my plugs were getting flooded, but I dont think that is the case now.

The car began bucking and snorting under 1/2 - 3/4 throttle, and over 15psi boost. After changing three sets of plugs, and temporarily disconnecting my alky, my car is now back to 16psi trim on 93 octane

Sunday I barely made it home. Stalled at a couple of lights, and I cant even get CLOSE to building boost. I barely touch the gas and it misses and backfires. I have no codes on the SM.

Tomorrow I am putting on new plug wires since I was going to get new ones anyways. FP is 47 line off (a little high I know but not enough to cause this)

If the wires do not cure the problem I am thinking MAF or coil pack. Any ideas?

 

[Carolinaturbot6]

Bob. you can check the the coil pack with a ohm meter. Check the resistance between the front & rear terminals on the coil pack. You should read between 11-13k ohms. Sometimes temps will affect the readings, but this is usually a reliable test 75% of the time.

It could very well be the maf. They don't always throw a code when bad. Bucking is a common symptom of the maf though.

How does the fuel pressure look? Is it rising ok? Has the fuel filter been changed lately?

 

[BLACK6PACK]

any scan tool data?

 

[blackbuick87]

I dont have a means to check the FP under boost, but the car is running so bad I cant get to boost anyways. O2's are ok, last time I was able to get on it (4 days ago) they were in the 820's.
MAF readings have been normal at idle, I didnt think to check them when I was praying to make it home Sunday.
I tried hitting the MAF while the car was idling and there was no change. Tonight I am going to try unplugging it.

When you say measure ohms from front to back of the coil pack are you talking straight across, ala cylinder 1 v. cylinder 2, etc.

 

[Carolinaturbot6]

Yes, from the front to the rear on each individual coilpack. S. Wood taught me that, so if it's incorrect, blame him.

Let us know what you find.

 

[blackbuick87]

Well I got my Magnacore 8.5 mm wires today (its great living 90 min from Ramchargers) and installed them. Its probably in my head but the car did seem to start quicker.

Anyways I took the car for a ride and knew immediately it was running right. After warming up I stepped on it and ran up to 16psi with no knock. I drove a few miles and it was fine, started to head home and got on it again, and it started missing and backfiring It seems like the longer I drive the worse it gets. It was not as bad as Sunday however when I barely made it home.

So I got home and with the engine hot and running, I rapped on the MAF. No change. So I unplugged it. My INT numbers dropped to 110 and BLM's started plummetting from 140's (normal for hot idle in park) to 120's and kept dropping. I tried revving it and it was missing above 2000 rpms. Put it in drive and it stalled.
Also when I was driving I was watching the MAF numbers and they seemed to be working normally and updating normally.

I need to find an Ohmmeter so I can check my coil pack.

Any ideas? should I order an LT1 MAF and translator or wait and check my coil pack further? Thanks

 

[blackbuick87]

ttt

 

[fly89gta]

my car showed the same symptoms when my POS remaned MAF died, lasted like 2-3 weeks

 

[Carolinaturbot6]

How old is your fuel pump? I'm asking because a fuel pump that's on it's way out will sometimes pump fine until it gets warmed up, or hot. Once it reaches a certain temp. it will stop pumping correctly.

Coilpacks will do the same thing. It wouldn't hurt to ohm it before buying a new maf setup.

Red Regal T sells coilpack/ignition module kits that are nice to have when troubleshooting. He tests them before shipping.

Let us know what you find.

 

[blackbuick87]

All right just to give this thread a close and help other guys in the future, I have driven the car the last two days and have had no more problems.
I ended up changing plug wires and the coil pack. I tested the old coil pack and all the resistance readings were in the mid 12.5 range. The new coil pack read all high tens across the board. Is this about normal for bad readings?