boost spike???

[b005t3d]

When you say a slight hesitation, what exactly do you mean? If you're at WOT with full boost and take your foot completely off the throttle for a half second, then slam it back to WOT again, *that* is what Fuel cut feels like. It's not just a hesitation, it hits hard and is rather difficult to mistake for anything else.

Does it do this at a specific point in the RPM band, or a certain boost, or is there no pattern to it?

Do you have a real boost gauge, or is your 10psi an estimate?

its hard to explain, it def does not feel like im taking my foot off the gass. it feels like the motor wants to keep going faster but has reached its limits. like it hits a wall. the 10psi is exact. i have an autometer boost gauge. it doesnt seem to have any pattern to it either. that why i originally thought it was boost sapike from the shitty boost controller im using.

 

[Mr. Y]

Same problem. Stock fuel/AFM + Suprasport turbo. I have not electronic boost controller.
I've got an idea: may be WG is jamming a bit and this causes little overboost. What do you think? If I am right, people with electronic boost controllers should not have such trouble.

 

[b005t3d]

Same problem. Stock fuel/AFM + Suprasport turbo. I have not electronic boost controller.
I've got an idea: may be WG is jamming a bit and this causes little overboost. What do you think? If I am right, people with electronic boost controllers should not have such trouble.

i have no idea as to how i would stop the waste gate from jamming without replcing it.

 

[GrimJack]

I doubt this is the wastegate. If this were sticking, it would spike to a higher boost initially, then be slower to close and start building boost again after a deceleration.

Does this happen at the same PSI reading all the time?

 

[Mr. Y]

I don't know. I'd describe problem as follow:
2nd gear, 2K RPM, Gas to floor - car accelerates, boost rises, then pause, then BIG kick in ass. I'm sorry, but I should watch for road - not gauge.
I'll try to hook ZT-2 to watch AFR, when this shit happens...

 

[b005t3d]

I doubt this is the wastegate. If this were sticking, it would spike to a higher boost initially, then be slower to close and start building boost again after a deceleration.

Does this happen at the same PSI reading all the time?

i doesnt seem to be at any kind of pattern but ill watch it today to see if it is.

 

[flatking]

Perhaps it's overboost? Do you have aftermarket exhaust and stock wastegate ? I don't know much about it yet, but maybe that'll put toward the right direction. the link is to a basic info site
http://www.st205.net/techinfo/turbasics.htm

 

[IHI-RHC7]

sounds like detonation to me...

 

[Mr. Y]

Well, I've discovered the problem - wastegate is sticking! But I have SupraSport turbo, so I dont know as for CT-26...

 

[suprafly]

ever have any luck with this? i ahve the same prob

 

[cruzinbill]

Yah i found the problem for mine i had then.
IHI-RHC7 was correct in my case it was detonation

 

[bigal0043]

oh that sucks were u able to fix the problem? was it because u were running 550s? and a stock afm?

 

[lagged]

detonation is caused by running lean. some causes: fualty injectors, too much boost, (or in my case...) failing fuel pump.

 

[cruzinbill]

lagged is correct here i had some injectors that were bad mixed in with a pump on its last leg

 

[bigal0043]

see this should go into the wideband thread that was going on... If you would have a wideband you could have seen that you were getting lean... i thought it was a bad idea to have 550cc injectors without the lexus afm? or was it the other way around havinga lexus afm and 440cc injectors...

 

[GrimJack]

Lexus + 440 injectors is bad.