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420A bad timing belt?

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PlanZero

Proven Member
1,516
263
Aug 13, 2013
Easton, Pennsylvania
On my girlfriends rs these symptoms have been getting progressively worse. Oil smoke like crazy after warming up, jumpy idle, bucking, hesitation, and loss of power. I changed plugs, wires, tps, IAC, battery. Compression is perfect. No problem starting. Oil looks OK, as well as coolant. I don't know when or if the timing belt has ever been changed. I'm trying to figure this out before I go dumping more time and money into a 420a.
 
Take the top timing cover of and inspect. Also rotate the crank either by hand or by bumping key and see if the timing marks line up. What are you compresion numbers? Was there any oil on the plugs when you changed them? The valve cover gasket and spark plug tube seals are known for leaking when old.
 
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Well had a friend 420a rs and had roughly same issues.

Valve cover is probably leaking somewhere or it's valve seals if it is exhaust bound smoke.
Best thing to do honestly mix 1/2 a bottle of lucas with oil changes or 1 full bottle depending on severity. I myself have never had an issue using lucas just never used it in a turbo (don't feel comfortable about it)

Bad baffle in gas tank or cruddy fuel filter, try changing the fuel filter out and run some high octane in it only (93 absolute max to go with) 3 of my friends cars have ran 100% better and stayed running better with the better / cleaner fuel.

With cleaner fuel running in it for a little bit open it up and give it hell to blow out what you possibly can.

PCV and EGR has probably never been changed so check into that.

Timing typically rarely will just jump usually it will loose teeth then jump and won't start or break.
 
I forget what the numbers were off the top of my head, but they were whatever a 420a is supposed to be. There was some oil on one plug, but I changed the vc gasket and spark plug seals, and no oily plugs since. Also changed the pcv. This thing blows a ton of smoke. Also erratic idle until warmed up. And by bucking I mean that when I hit the gas, then lay off, then tap the gas again it bucks. This effing weather is making everything worse. Arrrrgh!
 
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