1985 Plymouth Reliant will not idle

1985 PLYMOUTH RELIANT
450,000 MILES • 4 CYL • 2WD • AUTOMATIC
Avatar
BUTTERZOWEY
  • MEMBER
  • 4 POSTS
I have a 2.6L Mitsubishi engine with 450,000 Km on her. I took the engine out of my 1985 k-car and dropped it into a 1988 Chrysler Dynasty body. It has given me years of great service until now. The other day I drove it to work ( aprx 20Km ) and as I pulled in to park she died. it restarted right away, but it would not idle. I turned my idle way up so that it will idle, very roughly. I checked for any vacuum leaks and replaced the intake manifold gasket as it was leaking abit. It helped some but it still runs like a bag of hammers. When the engine is cold it runs fine but as it heats up the idle gets rough. I did a compression test and leak down test and they checked out my compression is running around 150psi in all four cylinders with no loss of compression. Unless I am missing something with these engines that leaves the carb. If that doesn't work should i take the head off, really do not want to as the head gasket is only a year old.
Jan 18, 2009 at 12:38 AM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,176 POSTS
If you have good copression, and you do, there is no need to remove the head. It really sounds like a vacuum leak. I would double check that, and also, make sure the choke is opening properly. Also, make sure the catylatic converter isn't plugging up on you.

Let me know what you find.

joe
Mar 22, 2009 at 12:26 AM
Avatar
BUTTERZOWEY
  • MEMBER
  • 4 POSTS
found the problem. removed the head and had it tested. It was cracked over # 2 ,running between the valves. Changed the head and now the engine runs like new.
Mar 23, 2009 at 10:07 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,176 POSTS
Wow! I'm surprised you had that good of compression with a cracked head. Regardless, I'm glad it's fixed. Let us know if you have questions in the future.

Take care,
Joe
Mar 24, 2009 at 7:41 AM