Thread: stock (allegedly) gtp with flow mods nets 10 degrees kr at wot?

i picked up a new gtp bout a month ago. hooked up the scan gauge to it. and its getting anywhere from 5 to 10 degrees of knock at wot and it started knocking last week. it has the power log on the front 3 inch dp into some cobbled together cat delete. zzp cold air intake 10.55mm wires and a zzp pcm. i changed the plugs in it yesterday to 103 autolites.... i cant figure out this car so any suggestions would be great. the afr at wot is 11.4. and it only registers knock sometimes but that is a bit high for my liking. plus with all the flowing mods on it why is it so high? fuel trims are zeroed out and between +- 5 at idle and beyond. fuel pressure at idle is 42. 52 without vacuum and i cant test it on the fly. ...help?

Seems like a lot of knock.


Have you checked the condition of your mounts...maybe it's giving you false knock?

What about changing the PCM out in favor of another vendors or maybe even trying the stocker?

I also assume it has a stock pulley. And SES codes? What year is the car?

stock pulley. motor mounts look new and look a bit shorter than what ive seen on my old car. car is a 1997 the knock typically peaks around 5k on the tach. if it has any pattern at all. no ses lights.... im sorta leanin towards a new ignition module. the tps iac valve maf and iat sensors are new. the guy had the receipts from oreileys. seems he knew somethin was up with it -_-

I wouldnt be running 103's in that, far far too cold.

But thats only part of the issue the car has.

id be wary of anything made by ZZP, especially if its the PCM

i got a set of ngk tr6es layin around ill put them in and see if it helps. yeah i was worried about the pcm as well but i dont think it would show up as intermittent as it does. on a side note the suspension is roughed up enough that the car wheel hops off the stoplight under moderate throttle. idk if that would cause knock at high speed tho. ill run some vp race gas through it tomorrow after work and test it out. see what it does.

Sure the downpipe isnt hitting the swaybar?

I'd say something is hitting somewhere. I had more kr on my zzp pcm then i did stock btw

Originally Posted by txslow6

Sure the downpipe isnt hitting the swaybar?

That's my guess.

mixed in 2 gallons of vp race fuel. tried the tr6 plugs. no change took em out. white buildup on the ground straps. too hot? i failed to disconnect the boost bypass to check if its just from boost but im sure its not. its cooler today and the car registered 13 degrees kr at mid throttle... its gotta be false knock. the downpipe isnt hitting the swaybar but it does have a bit of give to it. there is also bearing noise on the pulleys. im not sure which but it seems to be the ac/ which doesnt work anyway. replaced the ignition module. minimal change. its not always at the same rate mostly cuz i can hammer it in first and itll run fine till 2nd then itll build a bit of kr. at 70-75 mph it hits double digits. every time at wot and usually at cruise speed. the suspension in this car is shot. the rear brake rotors are grooved and i have a suspicion that the ball joints and whatnot are on the way out too. im not worried about the car cuz the body looks like it was hit by a cement truck. the motor is goin somewhere a tad lighter. but the kr issues worry me. and i have no experience with false knock. =/

ok... im not familiar with the knock sensors. but i pulled the super charger belt off today and drove around. between 4 and 5 k rpm it registered 10+ degrees of kr. i no this shouldnt be possible at all. so it is false? is any kr possible on these motors with the boost taken away?

10* with no boost? something is up...

hooptie suspension is my guess. or a very angry transmission

Originally Posted by Leiliel666

ok... im not familiar with the knock sensors. but i pulled the super charger belt off today and drove around. between 4 and 5 k rpm it registered 10+ degrees of kr. i no this shouldnt be possible at all. so it is false? is any kr possible on these motors with the boost taken away?

yup its false... Something is hitting. and run al 605s or 606s btw

i'd swap in a stock pcm and see what happens, also search, swapping knock modules in 97 year model pcm's

ill pick up some autolites on payday i think. the ngk plugs i tried i didnt much agree with. switching knock modules... how do i go about askin the guy at autozone for a lt4 knock module without him having a stroke lol. btw. the wheel bearings tie rods and struts on the front are all rather well worn. im not sure if this could cause false kr. but im pretty sure the top of the strut mount isnt sposed to spin freely. im not worried about the car itself. i have another 97 that had alot of craziness done to. i just want to try the same style motor in a smaller car. but i want to make sure the engine is in good shape before i frankenstein it

ok. i misread that. apparently it wont fit. what kind of knock modules can i swap for the one i have? given that the module isnt the direct culprit itself

its inside your pcm if i remember correctly. should be two. you swap them, Left to Right and vice versa.