B18c turbo misfire/stutter
#1
Honda-Tech Member
Thread Starter
Join Date: Oct 2013
Location: Red Deer, AB
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
B18c turbo misfire/stutter
Engine is a p72 Gsr with a t28 turbo, 650cc injectors tuned on hondata s300 at 8psi. Has a new distributer and plugs. I'll attached a video of it idling hopefully someone has some ideas I've been chasing it for about a week
#4
Honda-Tech Member
Thread Starter
Join Date: Oct 2013
Location: Red Deer, AB
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Re: B18c turbo misfire/stutter
Car had a slight misfire on the dyno but only at idle and was assumed it may be a bad distributor, I replaced it and it's still there. It has got slightly worse in the past week since I've replaced it but I have good spark so I assume it's a fuel or vacuum issue.
#5
Honda-Tech Member
Re: B18c turbo misfire/stutter
It's a bit hard to hear in the video and I don't have the best headset available right now, but based on the idle behavior I would suspect a vacuum leak.
#7
Honda-Tech Member
Re: B18c turbo misfire/stutter
Vacuum leak still seems most likely to me just based on it's behavior. I've pulled some absolutely atrocious looking plugs from 25+ year old cars that have had minimal maintenance done on them, probably 150K+ on some cheap plugs, and while they obviously weren't optimal they never impacted the idle or caused a fluctuation like this.
Low coolant is an interesting thought and would also impact IACV, if OP hasn't checked that.
Low coolant is an interesting thought and would also impact IACV, if OP hasn't checked that.
Trending Topics
#8
Honda-Tech Member
Thread Starter
Join Date: Oct 2013
Location: Red Deer, AB
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Re: B18c turbo misfire/stutter
I will check the coolant level this afternoon, I did notice that the upper rad hose seemed to have vacuum on it when I was checking compression. It basically sucked it self closed at some points, When i looked a week ago it was definitely full of coolant.
#9
Moderator
iTrader: (14)
Re: B18c turbo misfire/stutter
Even the reservoir being full, make sure the system is Air-bubble-free. I've had quite a few times where I would think something is wrong by way of a vacuum leak or IACV, only to find that coolant in the system was low. Once filled, the intermittent idle went away immediately.
#10
Honda-Tech Member
Thread Starter
Join Date: Oct 2013
Location: Red Deer, AB
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Re: B18c turbo misfire/stutter
Checked the coolant and its all good, out of curiosity I replaced the rad cap and it cleaned up my idle still a slight bobble but not nearly as bad as it was. I haven't had a chance to take a boot around to get it warmed up real good yet. Definitely confusing, any idea as to why it would have been the rad cap?
#11
Honda-Tech Member
Thread Starter
Join Date: Oct 2013
Location: Red Deer, AB
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Re: B18c turbo misfire/stutter
Back to doing the same thing again today, (the stutter that is, not the suction on the coolant hoses). Gotta find some time to take the IACV apart and clean it, I guess that would be my next step.
#12
Honda-Tech Member
Re: B18c turbo misfire/stutter
Spray carb cleaner on/around all the vacuum lines, anything leading to the intake manifold or to the head. See if you find any leaks.
Edit: Left a comment to check AC compressor clutch, then realized you have no AC.
Last edited by Chance EG; 10-09-2017 at 02:01 PM.
Thread
Thread Starter
Forum
Replies
Last Post
Key Enzyme
Engine Management and Tuning
7
03-29-2013 08:24 AM
PM-Performance
Forced Induction
21
02-03-2004 10:10 AM