XJ6 & XJ12 Series I, II & III 1968-1992
Sponsored by:
Sponsored by:

It Lives!!! But shakes badly at idle and during acceleration.

Thread Tools
 
Search this Thread
 
  #1  
Old 12-17-2012, 06:00 PM
84bluexj6's Avatar
Junior Member
Thread Starter
Join Date: Nov 2012
Location: WPB
Posts: 17
Received 0 Likes on 0 Posts
Default It Lives!!! But shakes badly at idle and during acceleration.

Thanks to everyone!!! My xj6 started, the trick was to have my wife crank the motor whilst I gyrated the AFM. She's always been luckier than me. I guess that's what I needed. Thank you.

But it's running real rough at both idle and under accel. It used to do this at cold startup but when revved the engine it would stop this bad behavior for the day until the engine cooled over night, now it won't go away, it maybe worst. I'm wondering if its the same issue or a different issue? The engine doesn't really get all the way up to temperature. Runs a little cooler than usual.

I Did the compression test and all cylinders are at about 140-145 except #6 at 135 but it came up with the wet test. I have spark at all cyl. I have voltage at all injectors. I unplugged the injectors to all of the cyl one at a time while the engine was running and it would shake more every time one was disconnected EXEPT when I unplugged the #1 cyl. No change in shaking although that injector is working. I watched it in action when I was testing the computer. If I would unplug the #2 (or was it #4) injector the engine would smooth out. ?????

Where to check?

Damage to the AFM when I blew it off with an incorrect firing order? Not sure if that would cause shaking at all rpm's.
Harmonic balancer problem from sitting (not sure how a weight goes bad)?
Bad injector? The exhaust makes me want to cry its so rich.
Can I play with the vacuum advance to see if it smoothes out?

Thanks, I will pay it forward. -David
 

Last edited by 84bluexj6; 12-17-2012 at 06:29 PM.
  #2  
Old 12-19-2012, 10:45 AM
JagCad's Avatar
Veteran Member
Join Date: Jul 2012
Location: Walnut Creek, California
Posts: 6,796
Received 2,399 Likes on 1,880 Posts
Default

Disconnecting the number one injector and making no difference is a classic indication that number one isn't running. So, a six cylinder engine on five will rough rough and lack power.

Now, why dumbing out 2 or 4 would smoothen the engine leads me to pure conjecture.
Chjanging an unbalanced five to a better balanced 4?

The compression is decent enough to make the engine run well.

I recommend carefully rechecking the foiring order and the rotor rotation to see if spark is being directed to each cylinder and actully getting there.

Now, if the dampener is failing, the outter rim is slipping around on the inner. A minor dampening issue, no effect on cyinders firing. But, what it does do is make the timing mark out of sync with the cylinder location. Pointer at TDC no longer means that 1 or 6 is actually at TDC. Thusly, you have no idea as to somewhere between.

If you want to verify TDC vs pointer, come back and I or another will set a path for you.

First, get the firing order verified.

Carl
 
  #3  
Old 12-24-2012, 09:05 AM
84bluexj6's Avatar
Junior Member
Thread Starter
Join Date: Nov 2012
Location: WPB
Posts: 17
Received 0 Likes on 0 Posts
Default

Originally Posted by JagCad
Disconnecting the number one injector and making no difference is a classic indication that number one isn't running. So, a six cylinder engine on five will rough rough and lack power.

Now, why dumbing out 2 or 4 would smoothen the engine leads me to pure conjecture.
Chjanging an unbalanced five to a better balanced 4?

The compression is decent enough to make the engine run well.

I recommend carefully rechecking the foiring order and the rotor rotation to see if spark is being directed to each cylinder and actully getting there.

First, get the firing order verified.

Carl
Wellp, I checked the dip stick and found 7 liters of gray oil in the crank case. I checked the oil 2 days before the car died and it looked good. Could it be something else other than a blown head gasket? Water in the intake from flooding or the water that I had in my gas lines and tanks?
 
  #4  
Old 12-25-2012, 12:02 PM
JagCad's Avatar
Veteran Member
Join Date: Jul 2012
Location: Walnut Creek, California
Posts: 6,796
Received 2,399 Likes on 1,880 Posts
Default

Seems a stretch to me. Flooding means excess fuel. And, it would mean lots of water through the injectors to emulsify the oil in the sump.

So, drain that oil. If the first liquid that comes out is clear, it is water in the oil!!! Oil floats on water. Then put some in a glass container and leave it for a time, Observe, a day or so. Oil will float up, leaving a clear layer of water at the bottom.

Has the coolant level gone down? Head gasket failure symptom. Apply air pressure to each cylinder, especialy no1. Gurgling in the water tank. Gasket failure. Is the 1 plug nice and clean when compared to the others? A form of water injection does this. Gasket failure.

However, I am not satisfied that the correct wire is at the correct plug. An engine with good compression even with a gasket weep should run decently. Not a great thing, but indicative.

Off to start the Xmas ham!!! Daughter coming over with the labor and trimmings.

Happy Holidays to all
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Bcrary3
XJ XJ8 / XJR ( X308 )
35
02-21-2023 04:29 AM
ccfulton
XK8 / XKR ( X100 )
4
09-20-2015 05:15 PM
explorer364
XJS ( X27 )
3
09-11-2015 05:44 PM
teacoff
F-Type ( X152 )
15
09-10-2015 08:25 AM
Bowman
XK8 / XKR ( X100 )
6
09-03-2015 03:17 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: It Lives!!! But shakes badly at idle and during acceleration.



All times are GMT -5. The time now is 08:22 AM.