Turbotweak help

93BlackTyphoon

93BlackTyphoon

New member
So I got the VeloSyTy chip, after some issues with Code 59. So now I have the chip, and it seemed to work at first. The chip requires certain parameters to be in spec. I've gotten all but on. The IAC is supposed to be 25-30, mine is at 72 and above. The truck idles rich and cruises rich. The AFRs are typically between 10.0 and 11.5 at a 40 mph cruise, also it idles pegged at 10.0. The truck is also only making 3 lbs of boost. Has anyone else had any issues? All help is appreciated.
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Turbotweak help

Check your throttle body set screw. Above 30 means the IAC is compensating for reduced airflow by opening the valve. Conversely, an IAC reading of 0 means the IAC is closed and you likely have a vacuum leak somewhere.
 
93BlackTyphoon

93BlackTyphoon

New member
Re: Turbotweak help

I've been messing with the set screw. It's touching the throttle blade then one extra turn. If I adjust it anymore it idles really high.
 
-Wip-

-Wip-

Typhoon
Re: Turbotweak help

I cant offer any help but I will say I had the same issue with my chip. Could t get the iac below 50 and when I could, it would idle fine for a bit and shoot way up in the rpms. Your boost issue may be a bad map sensor. I had a brand new 3 bar in mine that must have been bad from the get go which caused similar issues. I Put a new one in and ran much better.
 
93BlackTyphoon

93BlackTyphoon

New member
Re: Turbotweak help

-Wip- said:
I cant offer any help but I will say I had the same issue with my chip. Could t get the iac below 50 and when I could, it would idle fine for a bit and shoot way up in the rpms. Your boost issue may be a bad map sensor. I had a brand new 3 bar in mine that must have been bad from the get go which caused similar issues. I Put a new one in and ran much better.
Click to expand...


Thanks man, this is helpful, just because a part is new, doesnt mean its good. The MAP on my scanmaster is with in spec though.
 
Don W.

Don W.

Stab it and steer it
Re: Turbotweak help

Mine does the random high idle thing fairly often. I just put up with it. By all means discuss the IAC issue with Eric. The way I adjusted the idle screw is to have the motor fully warmed up, start data logging and adjust the screw. It seems to take s a moment for the chip/IAC to "catch up" to your adjustments. I also bump the throttle often to make sure the IAC number returns to its set number. Once done this made a noticeable difference in the way my truck ran. Primarily in throttle response off idle. Also use the chip to adjust idle mixture which helped things as well.

HTH
 
E

Eric Sy GN

Donating Member
Re: Turbotweak help

We are communicating by email at the moment. Hopefully we'll get everything adjusted, IAC ,etc, and go from there.
Eric
 
93BlackTyphoon

93BlackTyphoon

New member
Re: Turbotweak help

Eric has been a great help, but I will give a rundown of what I've told him. The truck is getting way too much fuel, its idling at 10.4 on the wideband, cruise is also very rich, and the idle is choppy, sometimes surges. The fuel pressure, TPS, and MAP are within the perimeters of what the chip requires, the only one that isnt is the IAC, and its way off, i believe its trying to compensate for the amount of fuel being dumped by the 60lbs injectors. The fuel pressure is set to 42 lbs with the line off. Im very much at a loss, to be honest it idles and runs like it has a massive vacuum leak, but i cant hear one.
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Turbotweak help

Are your vac line valves in the right direction?

As I said, an IAC would try and open more if there were too little air.

Too much (vac leak) and IAC goes to 0. If your throttle blades open slightly, does your IAC close all the way? You mentioned a high idle if you do...
 
WyoSyclone

WyoSyclone

Active member
Re: Turbotweak help

93BlackTyphoon said:
Eric has been a great help, but I will give a rundown of what I've told him. The truck is getting way too much fuel, its idling at 10.4 on the wideband, cruise is also very rich, and the idle is choppy, sometimes surges. The fuel pressure, TPS, and MAP are within the perimeters of what the chip requires, the only one that isnt is the IAC, and its way off, i believe its trying to compensate for the amount of fuel being dumped by the 60lbs injectors. The fuel pressure is set to 42 lbs with the line off. Im very much at a loss, to be honest it idles and runs like it has a massive vacuum leak, but i cant hear one.
Click to expand...

Ask Eric if he has compensated for the 'Injector DC Offset' of the 60lb injectors.
If not, it will do exactly what you're describing. Haven't seen many people address that important spec when tuning.
 
93BlackTyphoon

93BlackTyphoon

New member
Re: Turbotweak help

Update: The IAC was bad, the truck is actually a bit lean at idle now, lol. Need to tweak the idle screw adjustment a bit more. Found a big exhaust leak too at the crossover pipe, unrelated but it my explain why the truck only makes 3 lbs of boost. Thanks for your help guys. Much appreciated
 
D

Davemc1963

93 Ty Owner
Re: Turbotweak help

Just a thought to add. A worn throttle shaft housing on the throttle body can cause the throttle shaft to hang up/bind and not return to its stop. I had, (still have, another long term project!) this on a tpi vette that uses the same basic throttle body. High idle after cruise or running and coming to a stop. Blip the throttle and it usually 'shuts' properly. Its handy to know before you go resetting your IAC valve to make sure your throttle blades are actually in their closed position.
 
Syclone#2960

Syclone#2960

What ever it takes!!
Re: Turbotweak help

the question is did this happen after the chip install or is it a pre-existing condition? No sense is dumping in parts if its simply a minor tune issue.
 
93BlackTyphoon

93BlackTyphoon

New member
Re: Turbotweak help

Truck ran fine before I upped the injector size. Ran good on Code 59 too until something happened. Well here's an update. I found a big exhaust leak, and I changed the plugs which had been gapped wrong. No, the truck cruises wonderfully with the AFRs bouncing between 13 and 15. Every now and then it'll stumble and go very lean, then recover. Then when the truck is in gear the AFRs bounce between 15 and 17, the truck surges and sometimes dies from what seems to be lack of fuel. Also the truck is only making 5 lbs of boost. Also, how much vacuum do our trucks make at idle in park and in gear?
 
E

Eric Sy GN

Donating Member
Re: Turbotweak help

Sounds like its having some issues with closed loop if the a/f is swinging back and forth like that. I think you said you were using a stock O2 sensor in there, but you also had a wideband connected to pin F14. If that's the case, you can turn on option switch #4 on the chip, which will cause the program to start using the wideband for low end closed loop, instead of the stock O2. See if that helps at all.
If not, then we'll have to get you set up with logging so I can see what's happening.

Not sure on the low boost. What type of wastegate setup are you using?

Regards,
Eric
 
93BlackTyphoon

93BlackTyphoon

New member
Re: Turbotweak help

I'll try the #4 setting eric. Also all sensors are withing the parameters you suggest now. IAC is finally normal. It's a stock wastegate with stock boost solenoid currently.
 
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