HELP! Severe acceleration lag

juld0zer · 06-17-2014, 03:39 PM

i have 52000km so about 33k miles. Throttle bodies appear fine but i have never removed them from the manifold collector tk inspect the dirty side. I have bypassed the coolant lines completely so they do feel stone cold after a good run - would that cause an issue? Definitely no subzero temps here though so i doubt ice formation.

i have a Scanguage II in my car so i can watch some parameters live. When i am experiencing the issue, throttle position (TPS) gets pegged at 25 degrees max. Even with my foot to the floor.

What do you guys think about the MAP sensor theory? if the throttle plate opens no more than 25deg under full load then there would be a lot of vacuum right? I'm not sure how vacuum for brake booster is managed on our engine but my guess is that under certain conditions, the throttle flap closes slightly to generate vacuum - thus avoiding the need for a separate vac pump

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Loss acceleration.... Help...	camapthaman	Engine & Drivetrain	21	06-12-2014 05:26 PM
Severe Weather Warning NE	Mikes350z	North East Region	7	07-20-2012 10:01 AM
I've joined the wrecked Z club... [not as severe]	DIGItonium	Nissan 370Z General Discussions	79	04-07-2011 12:51 AM
rpm and acceleration problems?	3zzz	Nissan 370Z General Discussions	8	04-27-2010 02:12 PM
Man with severe brain condition died after being locked in cell for being 'drunk'	AK370Z	The Lounge (Off Topic)	0	11-21-2008 01:03 AM

06-17-2014, 03:39 PM	#11 (permalink)
juld0zer Enthusiast Member Join Date: Nov 2012 Location: Sydney Posts: 428 Drives: 11 Nissan 370Z MB M6 Rep Power: 139	i have 52000km so about 33k miles. Throttle bodies appear fine but i have never removed them from the manifold collector tk inspect the dirty side. I have bypassed the coolant lines completely so they do feel stone cold after a good run - would that cause an issue? Definitely no subzero temps here though so i doubt ice formation. i have a Scanguage II in my car so i can watch some parameters live. When i am experiencing the issue, throttle position (TPS) gets pegged at 25 degrees max. Even with my foot to the floor. What do you guys think about the MAP sensor theory? if the throttle plate opens no more than 25deg under full load then there would be a lot of vacuum right? I'm not sure how vacuum for brake booster is managed on our engine but my guess is that under certain conditions, the throttle flap closes slightly to generate vacuum - thus avoiding the need for a separate vac pump