Lola is getting new knock sensors.

Now, I will see what a Q45 can do!

The trip back to Alabama will be fun!

Cool. I have to get mine done also. Just imagining the feel of a 100% running 90 Q45.

me tooo ordered from Wes going in next weekhappy happy

I have spent over 4 hours doing mine on Y33. I found a way to do it w/o taking plenum off.You cut/bust your hands, but save on time and hassle of removing plenum.Actually, doidn't make any difference. I guess mine were fine before.I did it just to be sure that KS won't cause any problem in future!Cheers!

Please let me know or do a write up on how to replace the KS without plenum removal. I need to do this very soon. This would help a lot. thanks

Plenum removal on VH41DE not nearly as intricate as VH45DE. Was that much effort saved?

Just by looking at the 2, the 4.1 looks like it would be a harder job.

Q41 is 20% easier

All you have to do is drain coolant, remove alternator, remove upper t-stat housing with upper rad hose, remove (under the runners) rubber hose and you are in! get a stubby end wrench and go at it!It's gonna be tight in there. Take your timme and you get it!

Be ready to fight the hose that is under the air runners, it's a bear to get it out.

I have no problem removing plenum, I have problem with getting all the gaskets and replacing them Cheers!

And if you do drain coolant and open upper t-stat housing up, replace t-stat it's a breeze to do when you have all that off the engine + alternator. I found the t-stat in my Y33 was dated 9/96. Once you get it all off, you will see where the rabbit's den leads! \Cheers!

Ya know, looking at a Knock sensor, you wouldn't think it could help much of anything. I mean it doesn't look impressive at all and it doesn't even look like much more than a spacer or something. Without good ones our cars would have issues, but with them both our cars run great. I really can't think of anything else so small and plain the have such an effect on our Q's.

red

Timing is everything! KS helps to determine right timing in different driving conditions.

I have heard the knock sensors can retard the timing as much as 8 to 10 degrees, if necessary. That is a lot of lost timing advance! What is the use of VVT, it the knock sensors screw it all up.

I am picking her up tomorrow afternoon, for the ride home. I can't wait.

More than 10 degrees retard if the knock is more than ocassional.Builds up in steps as each rpm could have 4 knocks.........knock count per second.......at 2000 rpm =33.33 revs per second, could have 133 knocks per second.......unlikely that all 8 cylinders are knocking......you usually hear just the bad cylinder as once it starts very difficult to stop......unless you let of throttle or take out massive advance.

The problem with old cracked KS is they change sensitivity and frequency response.......when they should be signaling early to just take out a few degrees, the old ones signal late , WHEN it is too late, so the ecu goes way beyond the normal to try to stop the knock.

When it goes to severe retard there is a long time lag before it tries to add more timing back vs when it removes 2-3 degrees it retries every [1/10 sec] to add timing.......vs may be every 5 or 15 seconds when the count was severe.

The easy [with a Consult] test is to graph the advance under WOT in 1st gear 30-50 mph to make sure the advance gets to ~~27-28 degrees above 6,000 rpm.

The KS/ecu cannot discriminate knock from engine noise above say 3500-4,000 rpm [especially with old KS] so old KS tend to limit above 4,000 rpm power......better safe than a new engine.

THE KS ecu code just tells you of a total failure not old cracked performance......for that you must analyse the timing advance curve.

Long before you get a code the performance has declined.When you change plenum hoses at [every] 80-120k, change the 2-KS and harness. If you care about optimizing performance.

Each knock signal adds to the charge on a capacitor while a variable resistor [based on rpm] tries to discharge the capacitor. As the voltage creeps up or tries immediately the voltage tells ecu how much timing to remove.

For a real explanation study the following:http://www.intersil.com/data/an/an9770.pdf

Thanks for the information. I will have to print that out, and do some deep reading.

The car runs so much better, that when I merged onto 20 West, from 285 South, I nearly hit the car in the center lane in front of me. I had to merge all the way to the far left lane to miss her.

Before, I could really tell how the power would taper off when the engine got above 4500 RPM all the wat to the shift point. Now, it seems a lot more flat, and pulls all the way to the shift.

Thanks for the print out. I always like to have some proof that my car is running up to spec.

I enjoyed driving your Q, on your "test track" I definitely want the JWT ECU, now.

When I got in Lola, I just had to do the same test. Shedid well, but she's no first-gen Q. That extra weight, and softer shifiting makes a difference. Even with 164,000 less miles on her, I wouldn't put money on Lola in a race against your Q.