Another injector question thread (1994 Q45)

[Jeff Williams]

I had the fuel rail flushed and a consult ran at the dealership on Lola. When I went to the Dyno, it seemed that the power was down a bit (maybe not). The car never seemed to have the power Layla did. The fuel mileage has always been less on her than Layla. The previous owner had several injectors replaced, if not all. It was a California car, but has spent the last 35,000 miles drinking Alabama gas.

Well, I was reading up on injectors, and was thinking that mis matched, or clogged injectors could be the cause of my perceived lack of power.

This leads to my questions:

1. Is there aconsult read out that will give me individual injector readings?2. Can I tell from the consult, if the ECU is having to compensate for dirty or failing injectors?3. Is there another test I could get the dealership to perform, to see if the injectors are all firing equally?4. If I replace the injectors, is there a preferred model or size?

Thanks for the information.

[elwesso]

The power balance does all of this... Have them do the PBT and post the results!

[DominickJ30]

I dont think a Power balance test could check for dirty injectors as there would still be some flow and you will notice a drop in RPM anyway.

Unless you can match RPM drop?? Maybe Q45Tech can chime in on this.

What range is the power lacking on Lola?? How is the TPS, MAF, and IAC?

[elwesso]

I dont think a Power balance test could check for dirty injectors as there would still be some flow and you will notice a drop in RPM anyway.

Unless you can match RPM drop?? Maybe Q45Tech can chime in on this.

What range is the power lacking on Lola?? How is the TPS, MAF, and IAC?

All injectors shoudl be within say 10-15 RPM of each other....... So it would certainly show dirty injectors.

[Jeff Williams]

It seems that she doesn't have the instant-on power that Layla did. Layla could roast the tires once they started spinning. Lola wants to bog after a bit. Of course the tires are 1" wider on Lola. She is much better since yron replaced the knock sensors, and the NICO ECU helped some, too. The dealership checked the IAC and TPS are fine. The MAF is fine. The air filter seems a bit dirty, so I will clean it.

I have run out of spending money for a while, so I will watch and wait.

I don't know what my next mod will be.

I have asked for a power balance ,but I didn't get any results.

Can someone explain exactly what is involved with a power balance?

I have to return for the 3rd belt to be installed and show the guys my new exhaust. Maybe they will do a free Consult, since I have the new O2 sensors installed.

[Q45tech]

You must never run out of money as a Q owner.............don't you hear those magical alluring voices in your dreams suggesting you take a 2nd or 3rd job to pay for the Q proper upkeep. This is from a secret module buried in the dash [not described in FSM]...................all expensive lux sporty cars have one.

When the automatic idle rpm compensation is disabled by Consult and you kill spark and injection sequentially.......each 7 cylinder combination should show exact the same rpm drop if the 7 cylinders produce the same torque as the dead cylinders friction should be the same.The rpm ratio of 8 vs 7 cylinders............should be X% less plus friction of dead cylinder ...........the idle is bumped up by consult to increase resolution.

I always do a 2 step version..........unloaded in Park and loaded in Drive [foot on brake].

Consult I averages up or down in 12-13 rpm groups for a +- 0.5% ACCURACY......................good enough.

With a 1200 rpm [all 8] a 75 rpm drop is normal for 7 cylinders but 62-87* is ok................AS LONG AS THEY ARE CONSISTENT!

Varies depending on base rpm.