1994 Toyota 4x4 develops miss after warm up

I recently installed a new/rebuilt long block into my 1994 Toyota 4x4
pickup. During the install I encountered a problem where I was getting
a large amount of water in the oil pan. The problem was an alignment
pin on the timing cover...I had two in one hole. I repaired the leak
and been driving it to work for the past week.

At initial start-up and during 95% of the drive (25 min highway drive)
I experience no problems. When I park and let the truck drop to idle
speed there is a miss. I have noticed it at a stop light after about
20 min worth of driving. It does the same thing on the way home starts
fine idles fine during the first part of my trip, but once i make it
home the miss is back.

Any ideas? Could it be related to residual water in the oil from the
initial leak? Spark plug wires (the only part i didn't replace during
the install of the rebuilt longblock)? Could the valves need adjusting?

"Brad" <stratmaster@peoplepc.com> wrote in message
news:1143117731.210651.90110@z34g2000cwc.googlegroups.com...[color=blue]
>I recently installed a new/rebuilt long block into my 1994 Toyota 4x4
> pickup. During the install I encountered a problem where I was getting
> a large amount of water in the oil pan. The problem was an alignment
> pin on the timing cover...I had two in one hole. I repaired the leak
> and been driving it to work for the past week.
>
> At initial start-up and during 95% of the drive (25 min highway drive)
> I experience no problems. When I park and let the truck drop to idle
> speed there is a miss. I have noticed it at a stop light after about
> 20 min worth of driving. It does the same thing on the way home starts
> fine idles fine during the first part of my trip, but once i make it
> home the miss is back.
>
> Any ideas? Could it be related to residual water in the oil from the
> initial leak? Spark plug wires (the only part i didn't replace during
> the install of the rebuilt longblock)? Could the valves need adjusting?
>[/color]

It shouldn't be caused by the water leak but you should have changed the
oil if it had water in it.If you haven't already changed the oil, do it NOW.
Water in the oil can cause bearing damage, coolant in the water will speed
up the process. Spark plug wires should cause a miss under load, not at
idle. If the valves were not adjusted properly ( too tight ) it could cause
the symptoms you describe. I would recheck the valve adjustment. Did you
have this problem before the engine swap ?

<I would recheck the valve adjustment. Did you
<have this problem before the engine swap ?

I did not own the truck before the rebuilt engine was installed, so I
am unsure about the history. I can find out though and that is a good
point.

<If you haven't already changed the oil, do it NOW.

I drained the oil immediately after finding the leak. I also cleaned
off the head before filling the oilpan again. I ran the new oil about
120 miles and changed it again. I am going to run this oil about 500
before the next change.

< I would recheck the valve adjustment.

Do you think it would hurt to wait until the 500 mile mark. I can
retorque and check the valve adjustments at the same time.

"Brad" <stratmaster@peoplepc.com> wrote in message
news:1143146965.894113.34820@i40g2000cwc.googlegroups.com...[color=blue]
> <I would recheck the valve adjustment. Did you
> <have this problem before the engine swap ?
>
> I did not own the truck before the rebuilt engine was installed, so I
> am unsure about the history. I can find out though and that is a good
> point.
>
> <If you haven't already changed the oil, do it NOW.
>
> I drained the oil immediately after finding the leak. I also cleaned
> off the head before filling the oilpan again. I ran the new oil about
> 120 miles and changed it again. I am going to run this oil about 500
> before the next change.
>
> < I would recheck the valve adjustment.
>
> Do you think it would hurt to wait until the 500 mile mark. I can
> retorque and check the valve adjustments at the same time.
>[/color]

It might not hurt to wait but if you are having problems it might be a
good idea to check them sooner.

< It might not hurt to wait but if you are having problems it might be
a[color=blue]
>good idea to check them sooner.[/color]

I am bringing the core back to the machine/rebuild shop in the morning.
I will run it by them and see what they have to say about it.

Thanks for the tips. I will post my results.

R/
Brad

Could a bad knock sensor cause this type of problem. Mine is broken
off. I have one on order.
I have no clue what the knock sensor does except for make my check
engine light come on.

Refresh...

******
At initial start-up and during 95% of the drive (25 min highway drive)
I experience no problems. When I park and let the truck drop to idle
speed there is a miss. I have noticed it at a stop light after about
20 min worth of driving. It does the same thing on the way home starts
fine idles fine during the first part of my trip, but once i make it
home the miss is back
*******

I have put close to 500 miles on the new engine. The miss seems to be
getting less and less noticable, but is still there. I replaced the
broken knock sensor, so I have no check engine light any more.

Also I talked to the machine shop that rebuilt my engine and was told
there was no need to check the valve clearance or retorque the head
bolts....