New Overboost/knock

[conlyn]

On the truck when purchased: (taken from scott kilpatrick's G.A.S.T site)
Johnson IC pump
Custom HTP Chip (would like to know more about it)
External Tranny Cooler
GM Deep Tranny Pan
Electric Fans (can i remove the stock fanshoud since these have their own?)
Rerouted IC lines
Catco Converter with muffler deleted
160dF Thermostat
EGR Blockoff
Autometer gauges

Added by me:
K&N 9x5 Cone Air filter in place of battery
Adj. FPR<~~~~~~~~ set at 43 with vacuum line removed(also tried higher)
Relocated Batt.
fuel filter
Walbro 255 HP
SS turbo2IC w/ HKS SSQV BOV
Gilbert Front Prop. Shaft
fresh tranny/engine oil/filters


I just got my truck back on the road after weeks worth of work on it (a/v and fuel system).

Now i am seeing huge boost spikes upto 24psi, with audible knock. i know i shouldn't be getting into the motor, and i have been real easy on it.

The truck runs fine until about 5psi of boost when i accelerate from 5 the knock starts in and the boost gets rather sparatic going from 7-20 or just sticking at 15 but with knock.
When rolled into it builds boost fine until about 15 psi then it starts breaking up.

Prior to it getting the fuel system and sitting for so long due to the stereo install it would run at 17-18 psi all day and not knock at all.

I know it's not the motor because it doesn't have any problem revving at all in neutral (no, i didn't hold it to the floor :roll: )

Where should i start looking
I checked the vacuum lines going to and from the boost control and the wastegate. i don't know if it is a turbo issue, a ecm issue or my truck is just falling apart but i do know i need to get it fixed, so i can go... do my thing again. because driving a typhoon isn't as fun when you can't go fast

gas is fl 93.
i need datamaster!!! my next 'mod' and a short while away(should have bought it first)

 

[sytyguy]

Re: New Overboost/knock

The chip was done by me. In fact I kept the truck for some weeks ironing out every possible issue, and (aside from the stock chip in the '92 Syclone) I feel comfortable saying it's the best stock style chip I've ever done (and I've done A LOT). Anything you want to know about that chip, just shoot me an e-mail and I'll be glad to answer.

One of the things that has me bewildered is the boost control. That truck had AWESOME control (that was the truck I designed all of my improved stock boost control mods around), and held boost ROCK SOLID. Have you modified the exhaust or WG rod in anyway? Aside from a solenoid failure, exhaust modification, WG rod adjustment, or vac line issue, I see no reason for it to spontaneously change that radically. When you did the battery relocate and air filter mod, is it possible a line got unplugged and hooked up incorrectly? I attached a pic of how they should be hooked up below.

If you still can't fix this problem by the 27th, then maybe swing down to Daytona with it and I'll check it out at the FAST/GAST meet.

BTW, I did considerable fuel work with that chip, so you may wanna keep the FP close to what I had it set at beforehand.

Hood

 

[conlyn]

Re: New Overboost/knock

could someone list the procedure for check/fixing the WG rod?
Also, it had the stock FPR on it before, so what FP do you think i should be running?

Going to test her out shortly.

And as far as the 27th goes, my finances aren't quite in order right now, but i'll see if it will work out, I'd love to ride down south and meet up with all of you who have much more knowledge on these trucks then me, i'm always looking to learn.

 

[conlyn]

Re: New Overboost/knock

Well, i found the problem...
When i installed the K&N filter the stock orange elbow comming off the turbo was leaning on the top of the wastegate (creating a 'pinch' in the vacuum line).

i just installed new lines anyway, and now she's holding boost right on :lol: