hesitation at 4000RPM and low boost, any ideas?
#1
Scooby Regular
Thread Starter
Join Date: Jan 2002
Location: Plymouth
Posts: 960
Likes: 0
Received 0 Likes
on
0 Posts
hesitation at 4000RPM and low boost, any ideas?
I have a MY00 uk turbo with apexi AVC-R boost controller and S-AFC fuel controller.
In recent weeks my car has started to hesitate and judder back and forward when im around 4000 RPM with light throttle. This happens in every gear. I have switched off the boost controller and have noticed that the car is only giving around 0.5bar boost without the controllers intervention (Shouldnt this be around 0.9?).
Do you have any ideas as to what could cause this and if so where i can source the relevant parts?
thanks for your help
Dale
In recent weeks my car has started to hesitate and judder back and forward when im around 4000 RPM with light throttle. This happens in every gear. I have switched off the boost controller and have noticed that the car is only giving around 0.5bar boost without the controllers intervention (Shouldnt this be around 0.9?).
Do you have any ideas as to what could cause this and if so where i can source the relevant parts?
thanks for your help
Dale
#2
Originally Posted by Eagle7
I have a MY00 uk turbo with apexi AVC-R boost controller and S-AFC fuel controller.
In recent weeks my car has started to hesitate and judder back and forward when im around 4000 RPM with light throttle. This happens in every gear. I have switched off the boost controller and have noticed that the car is only giving around 0.5bar boost without the controllers intervention (Shouldnt this be around 0.9?).
Do you have any ideas as to what could cause this and if so where i can source the relevant parts?
thanks for your help
Dale
In recent weeks my car has started to hesitate and judder back and forward when im around 4000 RPM with light throttle. This happens in every gear. I have switched off the boost controller and have noticed that the car is only giving around 0.5bar boost without the controllers intervention (Shouldnt this be around 0.9?).
Do you have any ideas as to what could cause this and if so where i can source the relevant parts?
thanks for your help
Dale
#3
Scooby Regular
Join Date: Apr 2003
Location: Cambridgeshire
Posts: 1,541
Likes: 0
Received 0 Likes
on
0 Posts
I have switched off the boost controller and have noticed that the car is only giving around 0.5bar boost without the controllers intervention
Does the car still hesitate with the boost lowered - with the boost controller switched off?
The hesitation does appear to be ignition/spark plug related and will become increasingly noticeable when the boost is increased.
Cheers
#4
Scooby Regular
Thread Starter
Join Date: Jan 2002
Location: Plymouth
Posts: 960
Likes: 0
Received 0 Likes
on
0 Posts
If i put the boost controller on i get about 1.15 bar of boost and no juddering after 4500 RPM, it only occurs at 4000 RPM and light throttle.
Sounds like i'm looking at either the Lambda sensor or the coil packs then?
Sounds like i'm looking at either the Lambda sensor or the coil packs then?
#5
Scooby Regular
Thread Starter
Join Date: Jan 2002
Location: Plymouth
Posts: 960
Likes: 0
Received 0 Likes
on
0 Posts
Delboy,
i thought with the boost controller off it would revert to standard boost which is around 0.9-1.0 bar i think on MY00. Is this not the case?
i thought with the boost controller off it would revert to standard boost which is around 0.9-1.0 bar i think on MY00. Is this not the case?
#6
Scooby Regular
iTrader: (2)
Wwitching the boost controller off will cause boost to be passed direct to the actuator rather then bled off via the boost control solenoid. The standard setup also uses a boost control solenoid driven from the ECU, but your boost controller probably uses it's own and has bypasssed the standard setup.
The cracking pressure for the actuator is about 8psi, so that's all you will get with the solenoid switched off or bypassed.
The cracking pressure for the actuator is about 8psi, so that's all you will get with the solenoid switched off or bypassed.
#7
Scooby Regular
Thread Starter
Join Date: Jan 2002
Location: Plymouth
Posts: 960
Likes: 0
Received 0 Likes
on
0 Posts
OK thanks for that info. It was obviously just a side effect of me trying to isolate the 4000 RPM thing and not enough knowledge
That still leaves the problem that it is going nuts at 4000 RPM, any suggestions about that?
That still leaves the problem that it is going nuts at 4000 RPM, any suggestions about that?
Trending Topics
#9
Scooby Regular
Join Date: Jul 2003
Location: Out of darkness cometh light
Posts: 1,457
Likes: 0
Received 0 Likes
on
0 Posts
If it was WOT hesitation, my money would have been on MAF as well. But as it's part throttle, I'd be thinking lambda sensor. If you perform an ECU reset (using the plugs and not the stupid "battery disconnect for an hour" method), if the CEL flashes within a few seconds of reset-driving, it probably isn't the lambda. If it takes ages to flash the all clear, or indeed if it flashes you a code 32, then I'd be phoning my local Motor Factor...
Thread
Thread Starter
Forum
Replies
Last Post
Sam Witwicky
Engine Management and ECU Remapping
17
13 November 2015 10:49 AM