Hesitates badly under boost

[TYCharley]

Hi Guy's.

New member and first post.

I have a problem, when I get to about 5# of boost, then the whole truck starts to shuddering and hesitating. What's up with that (no pinging or knocking)

Any idears??
Thanks for any help

 

[75Monte]

Welcome to the board. You have found the greastest resource of info for the SyTy.

Are you using the stock boost gauge? If so, you might not be anywhere near 5lbs, the stock boost gauges are notorious for being VERY inaccurate. The condition you describe sounds like the computer (are you running the stock chip?) killing fuel supply due to overboost (15+lbs of boost). This is usually caused by cracked vacuum lines somewhere in the wastegate solenoid system or a wastegate needing adjustment.

Have you read the FAQ and the Readme? Start there.

 

[TYCharley]

Thanks Aron.
I do have external boost gauge (showing) about 5#'s and I have the Hypertech Thermomaster Kit and Accell Cap,wires and coil.

You can keep it at about 5# and it pulls pretty good but try more boost and it starts to faulter.

 

[bdubb]

 

[Tooky]

You really ought to change your image to say read the "SyTy Readme".. it's far more useful. That, or else just have Keith delete the unfinished "FAQ" and rename the "Readme" back to the "FAQ" as it was best left that way AND that's how it originally was to start with.

Charley, any new SyTy owner would definitely want to do a tune up described here: http://syty.net/faq.htm but in your case you might also have an additional problem, possibly a broken motor mount or a front driveshaft on the way out? The way you describe it shuddering.. does it do it at high speeds of cruising as well?

 

[TYCharley]

Thanks guy's.

I have had my TY since new and been a member of the Old SYTY site for a long time. I have attended SYTY gatherings and I have read all the FAQ's and would not ask this question if the answer was that easy.

Hi TookyCat. I have a custom made 2"front driveshaft on my TY (many on the list have the same shaft) and No it does not stumble at high speed (100mph+)as long as you just keep the boost at or under 5#'s. It has been tuned up (probably should do Cap and rotor + Plugs soon;-))and it just started to stumble lately.

So again, thanks for any inputs good or BAD.

_________________
92 TYPhoon
2000 GMC 3500 454 dually
2002 Polaris Sportsman 700 Twin
2002 Polaris Sportsman 500HO Freedom
Robinson Cruso was the only one to have all work done by Friday

<font size=-1>[ This Message was edited by: TYCharley on 2002-03-03 16:46 ]</font>

 

[Tooky]

Do you have a scan tool like Datamaster? If so, what is it saying past the 5# point?

 

[TYCharley]

Hi TookyCat.

No, I do not have a scan tool.
Probably time to get one and I would like to get the best one.
Any recomendations??

Read on

I just downloaded the Datamaster software and I assume I'll need to purchase the cable from them. How about the ALDL interface adapter, do I need that also?

Again thanks for the info.


<font size=-1>[ This Message was edited by: TYCharley on 2002-03-03 18:06 ]</font>

<font size=-1>[ This Message was edited by: TYCharley on 2002-03-03 18:07 ]</font>

 

[Tooky]

That's the one, just mention you have a GMC Typhoon to make sure they set you up with the right one.