xk8 4.0 drivabilty upgrade
#1
xk8 4.0 drivabilty upgrade
okay, i love my car but its been bugging the crap out of me, it's just not quite 'there'. I have finally figured out the issue. Intake valve crud!
SYPTOMS: sluggish off of idle, pinging from 1800-2300 rpm, shifts too low/soon , flubby drivability.
So, i blew the heater return line the other morning, that's right, it crapped in my driveway on first startup thankfully. So while waiting 2 weeks for hoses from amazon ( still waiting) i basically got the red *** and lossened the intake manifold to see if i could fabricate a hose solution. Imagine my surprise lifting the intake manifold up an inch of two to get to the clamp and seeing a FILTHY intake passage in the head. I mean all of them had 1-2mm of oily black crap built up in them. Now i'd assumed i had carbon on the pistons causing the preignition but i never thought i'd have this level of deposits on the intake valves. SO, i soaked the closed valves in seafoam, then hit them with engine cleaner and a brush, used a rag to soak up as much excess as possible. used some 3/4 inch copper pipe to make a section of heater line and buttoned it up.
AMAZING! my off idle is SO much better, and now the care has enough power at 1800 for the stock shift points to not be an issue.
I'm assuming that the PCV must have been the cause. drives like a 30,00 mile car now. instaed of a 130,000 mile car. check you intake valve deposits while you in there next time.
SYPTOMS: sluggish off of idle, pinging from 1800-2300 rpm, shifts too low/soon , flubby drivability.
So, i blew the heater return line the other morning, that's right, it crapped in my driveway on first startup thankfully. So while waiting 2 weeks for hoses from amazon ( still waiting) i basically got the red *** and lossened the intake manifold to see if i could fabricate a hose solution. Imagine my surprise lifting the intake manifold up an inch of two to get to the clamp and seeing a FILTHY intake passage in the head. I mean all of them had 1-2mm of oily black crap built up in them. Now i'd assumed i had carbon on the pistons causing the preignition but i never thought i'd have this level of deposits on the intake valves. SO, i soaked the closed valves in seafoam, then hit them with engine cleaner and a brush, used a rag to soak up as much excess as possible. used some 3/4 inch copper pipe to make a section of heater line and buttoned it up.
AMAZING! my off idle is SO much better, and now the care has enough power at 1800 for the stock shift points to not be an issue.
I'm assuming that the PCV must have been the cause. drives like a 30,00 mile car now. instaed of a 130,000 mile car. check you intake valve deposits while you in there next time.
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yachtmanbuttson
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