bucks and spudders under boost?

slowryders · 04-01-2008, 07:37 AM

i got an 87 7mgte with 3" straight exh and a intake on it everything else is stock. dont matter what gear im in when the turbo boosts to full psi it starts to buck and spudder? i searched and i cant come up with anything that helps. the boost is not turned up at all and its still the stock turbo. also i changed the plugs out and wires. and its still there? everything seems to be working just fine it all checks out. and it idles fine and runs fine. pulls nice if i only boost about half way but as soon as i hit the full psi it doesnt wanna run right? help.

mkiiisupra · 04-01-2008, 11:34 PM

run a diagnostic

Micahwc · 04-02-2008, 03:11 AM

Sounds like a classic boost leak, I had the same problem with a 91 3000gt VR4. Check your vacuum hoses, make sure they are not worn. I just replaced mine with a hose techniques kit, many of the hoses were rock hard, some were cracked and starting to brake.

I think that a boost leak could also be caused by leaks in your intercooler pipes. If you have access to a boost leak detector use it, if not, try spraying soapy water over your hoses while idling the car. Bubbles should form where ever there is a leak, so I have been told multiple times.

If your problem is a boost leak such as this then it is an easy fix. Replace any leaking part and your problem should stop. Hope this helps.

04-01-2008, 07:37 AM	#1
slowryders Stock Join Date: Mar 2008 Location: Pennsylvania Posts: 5	bucks and spudders under boost? i got an 87 7mgte with 3" straight exh and a intake on it everything else is stock. dont matter what gear im in when the turbo boosts to full psi it starts to buck and spudder? i searched and i cant come up with anything that helps. the boost is not turned up at all and its still the stock turbo. also i changed the plugs out and wires. and its still there? everything seems to be working just fine it all checks out. and it idles fine and runs fine. pulls nice if i only boost about half way but as soon as i hit the full psi it doesnt wanna run right? help.

04-01-2008, 11:34 PM	#2
mkiiisupra Lexus & 550's Join Date: Sep 2007 Location: Las Vegas, NV Posts: 570 Blog Entries: 1	run a diagnostic __________________ 1990 Toyota Supra Turbo A/T ------------------------------------------------ Questions about oil? take a look http://www.supramania.com/aehaas/

04-02-2008, 03:11 AM	#3
Micahwc Intake Join Date: Oct 2007 Location: johnson city TN Posts: 30	Sounds like a classic boost leak, I had the same problem with a 91 3000gt VR4. Check your vacuum hoses, make sure they are not worn. I just replaced mine with a hose techniques kit, many of the hoses were rock hard, some were cracked and starting to brake. I think that a boost leak could also be caused by leaks in your intercooler pipes. If you have access to a boost leak detector use it, if not, try spraying soapy water over your hoses while idling the car. Bubbles should form where ever there is a leak, so I have been told multiple times. If your problem is a boost leak such as this then it is an easy fix. Replace any leaking part and your problem should stop. Hope this helps.