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1990 Mustang 2.3 #3 Cyl dead

Extremely unlikely that the worn cam is the culprit, though if it's worn that much it couldn't hurt to replace it once you fix the real problem. You're losing a LOT of compression in that cylinder. You could have any number of problems that can only be ruled out through testing:

  1. Worn rings
  2. Worn valve(s) or valve seats
  3. Blown head gasket
  4. Cracked head

Have your mechanic check things out before you waste money on the cam (which probably won't help anyway...if it was the cam you'd be losing compression all over, not just markedly on one cylinder).

Cheers,

Reply to
Ritz
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Worn cam lobes will result in not enough lift at thh valve, and likely no a loss in compression. I agree with The poster below. You have bad valve, bad rings, broken ring(s), or other related problem with hole #3.

If you want to keep the car, go to a wrecker and buy a 2.3 longblock and rebuild it yourself with help from a machine shop. Unfortunately a

1990 2.3 car is not likely worth a new eng>
Reply to
cprice

I have a 1990 2.3 Mustang that suddenly started a solid misfire with loss of power. When I asked if there was and unusual bang, crunch, clatter, etc. just before the loss of power the answer was no. When I went to drive the car home I am quite sure that for a brief second it ran on all four.

When I pulled the plugs all were fine except #3 which had large (not oily) deposits on the centre and side electrode.

I replaced plugs with new with no improvement. I quickly removed the plugs and tested compression, throttle closed and engine cool. This showed # 3 at

30 and rest at 90. Adding a bit of oil to #3 gave 40.

At the suggestion of a local rebuilder I removed rocker cover and checked cam. Sure enough the lobes were very worn, looked like about 1/16" had been worn off all lobes. When I reported this to the rebuilder he was quite confident this (cam wear) was my problem and suggested I install a cam kit (about $200) or bring head in for rebuild/cam kit.

Any advice/insight would be appreciated, especially as to why the cam would have been so severely worn.

Thanks

Reply to
Lloyd Cimprich

Does your Mustang have the dual plug heads??? Nor sure about the cars but the 2.3 with dual plugs has the exhaust side plugs as the "primary" ignition system...

Reply to
Jim Warman

No it only has one plug per cylinder. It is too bad as the car only has about 118,000 km (about 70,000 mi.) and otherwise is in really nice shape with original finish. Even the A/C and cruise control still work fine.

I just tried the compression again on #3 & #2 very cold engine.

#3 30 and 40 after adding 90 gear oil

# 2 90 and 120 after adding 90 gear oil

I am begining to suspect a valve but will have to get the car into the garage so I can take off the head and see.

Thanks.

Reply to
Lloyd Cimprich

I don't know if this is true on the trucks. Some passenger cars with the 2.3 have a vacuum port on the manifold for the AC. The canister they use for a reservoir is like a large tin can. It cracks and makes a nice leak that kills the intake valve. I'd check into it just in case.

Al

Reply to
Big Al

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