Expert: Ara Date: 2/23/2008 Subject: Do i need a new engine?
Question QUESTION: I have a 1991 Honda Accord that i bought from a guy who said all it needed was a battery. So i pulled it home, put a battery in in and got it to crank. When it started, the motor was missing really bad. Well we fooled with it and fooled with it, and we couldnt fing the problem. We checked the timeing. It was right. We did a Compression test on it. my valves are good. i cant find what the problem is. Do you know?
ANSWER: Have you checked all the spark plugs?
What is the compression reading?
Have you checked the mechanical valve timing to see if the engine valve timing is correct? (You'll need the valve cover off for this one).
Let me know what you find.
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QUESTION: We have as best as we could....the compression is reading 180 on 3 cylinders...and 140 on the other one. And we put brand new spark plugs in it.
Answer Possibility #1: Timing belt broke a tooth or two. Valve timing jumped & bent the valves in one cylinder. If there are bent valves, the compression check will not show. You will need to do a "cylinder Leak Down Test".
Possibility #2: Faulty spark plug wire.
Possibility #3: Fuel injector faulty.
Pull spark plug wires off one by one on each cylinder & check resistance on the wire. There should be 4K-8K Ohms resistance per 1 foot of wire.
Also check distributor cap & rotor condition.
Q: Have you removed the valve cover & set the engine to TDC?
Q: Have you checked that when the engine crank is on TDC the cam pulley marks are aligned with cylinder head & the "Up" mark points up?
