Here I am again.......last time I posted I was chaning my opti due to an extra long dowel pin killed my last one. I also changed the opti harness because of 3 spliced wires near the connector. It doesn't seem to burn the header coating anymore and has much better throttle response but....

Anyways....I have tried everything, new opti harness, new opti, check fuel pressure, have pcm4less tuning, check for leaks, enlarged IAC idle hole on TB, changed wires, plugs,.

After the opti swap, I scanned the car again, and shortly after my longterm BLM dipped into 108 for both sides. Left & Right short terms are anywhere between 50 - 80 blm's.

The car surges at times, it is hart to start after warm up, only starts with help of throttle. Poor performance, -100hp. Smells offly rich, and fouls my plugs within minutes and has terrible gas mileague. IT practically eats it.

It is showing QUAD DRIVER MODULE 1 malfuntion, which I have been told it is code 26. But I do not know if it relates.

The car throws no codes. But the scan tool shows QUADDRIVER1 ERROR and the TUNERCAT site says it is error code 26.

I need more suggestions. I need help. PLEASE!!!!

Car is 93 T/A Auto with XE230/236 cam, ported heads, long tube heades, 2800 stall, pcm4less tuning, 30# SVO injectors, and some other nice stuff.

 

Yes, QUAD #1 is code 26. Did you try removing the custom programming chip and see how it runs without it?

 

You think it will even run without it? I am in the process of installing my 22#'s back, to compensate for extra fuel.

I figure it is programmed for the #30, then actually physically putting the 22#'s should lean it out a little.

While I am it, i will remove the custom chip to see if I notice anything different.

Thanks

 

If you put in 22s and run the 30 lb/hr program it will be pretty lean. Remove the chip when you have the 22s in.
It may run a little crappy, especially at idle, but it should run. (stock program and injectors I mean)

 

How So? It the pcm thinks it has 30#injectors (offsets reflecting that) how would putting 22's make it run richer? Do they not flow less, and since the pcm thinks it has 30#'ers it will think it is putting enought fuel that it would normally put our with 30#'s , but in this case only firing through some 22#'s.

I dunno you are the expert.


Wouldn't a stock program even help, I mean would it run rich with it period, since no changes are made to reflect the heads/cam changes.

I will be trying new tuning soon.....

also sometimes I believe this thing acts like it is running in lump home mode or something.

 

A quad driver code usually means the PCM is hosed. I would try a stock chip like someone else mentioned to see how it runs.. The quad driver circuit is basically a series of grounds in the PCM to control various functions.

 

PCM hosed? YIKES now that is new. In matter of fact, it also gives me QUAD DRIVER 2 MALFUNCTION interminnently also. CODE 27 I believe. BUT the PCM does not throw them. But they do show in the scan tool.

 

It could also mean a ground wire for the PCM is not tight..It is most likely one of these 2 problems from seeing those trouble codes.

 

Damn, just burn it down and collect insurance JMO

 

Oooops... I'm sorry. Yes, you're right, it will run lean. I didn't read very carefully and thought of it the other way around (30 pound injectors with 22 programming)
AFAIK, Quad driver #1 is related to some emission device disabling/removal... I'll try to find more about it.

 

Emissions device removal....

I have taken out:
1.) the whole EGR set-up, even the solenoid. Block off both passages at the back of the intake manifold.

2.) The Air Pump.

3.) I also took everything having to do with the A/C.

4.) I also am considering taking out the EVAP canister, if I can.

Do you think code 26 has anything to do with this. I have been told that code 26 relates to EVAP something.

I dunno. Please help.

 

Update:

I changed my coil wire, changed coil back to stock (MSD coil is about 3 years old) and changed back to stock 22# injectors. I also placed some spacers between the head and coil bracket to help preventing heat soak.

These were the only changes (still using pcm4less tuning).....and I noticed the following.

Long Term BLMs, are a 122 now, still rich but nowhere near 108. Seems to have helped horsepower immensely, but I have yet not proved it. (could be in head, I have being driven my Z34 for months now).

BUTTTT, (there is always a BUT!!!! )

After heating up, I noticed my car changed idle quality, it began to seem rough, and the exhaust cadence seems to have dropped. I let the car idle for a while, and I noticed that my blms began to split. Left side of car was running very rich.

I then took a spray bottle and sprayed some water on all my header primaries. The water instaneously boiled out except on the cylinder 2. The water took time to boil out on this primary. So I figure, that this is my problem. It is not getting hot enough, so I figure it is not firing properly.......i checked everything, but it all looks good. wiring is on tight. (Wires are only 2-3 mths old).

I waited for night time and noticed that coil wire was arcing bad, replaced it with the original one, and no more sparks. Still no change though.

What can I check next?????

Thanks

 

Sounds like a bad tune.... too much fuel possibly.

 

I could be mistaken but I think the quad drivers are the fuel injector controllers inside the PCM.

-Dave C. '97 Z28

 

Dave,

What makes you thing Quad Drivers are in any way related to fuel injectors?

Just curious, I am open to all possibilities.