ewenpg

So I got to spend a few weeks after changing the timing belt and water pump, to enjoy my lovely LS, but the other day, when I started her up and went to drive down the street it started to lurched a lot.
So I took it straight back.
Now everytime I start her, she idles ok but at higher revs it hesitates in not perfect rhythm, but close to perfect rhythm.
I have:
- checked and cleaned spark plugs
- checked spark leads
- Coils seem to be fine but will re check
- coils are getting 12V power when on ignition
- distributor caps seem to be ok
- oxygen sensors are at 14.1 and 13.9 which I believe is in range
- can only get primary coil reading on one coil which is a worry??

When the car gets warm to hot it runs fine. And at high revs does not hesitate. This is a curly one.


If anyone has any ideas or possible solutions please let me know!! I hate having this beautiful car sitting there!!

ewenpg

Ok to update:
-I rechecked both coils they are fine
-I got the code it is P0340 Camshaft Position Sensor A-Bank 1 Circuit Malfunction
-I pulled the drivers side Camshaft sensor out and cleaned her up, checked resistance, it falls in the accepted zone. Put it all back together and took her for a drive. Drives fine but the engine light came back on despite having cleared the code.
Anyone had something similar to this? Could it be a short between snsor harness and ECU? If so how do I test?
Thanks!

ewenpg

So for those of you who may have read this post or for future reference, the problem was the timing belt. Despite quadruply checking it it was one cog out on the left camshaft. While putting it on the line on the timing belt that needed to line up with the line on the engine block was never 100% in line. It was about 70% one groove and 30% for the other. Obviously I went for the 70% but apparently that was not the one. I slipped it back to the right groove and now she is perfect!

Neofate

iTrader: (1)

Great! You sound like quite the mechanic. Is the timing belt new?

Och

iTrader: (3)

Hehe, when I replaced my timing belt, the first time around I was off by about 5-10 grooves on the right cam. Thanks god it's a non interference engine.

ewenpg

Yeah new timing belt and water pump. I also changed rotors, distributor caps, belt tensioner and idler pulleys (both). I checked all the sensor resistances crankshaft, camshaft etc). Just that damn line on the belt that threw me off! So glad it is not interference engine!!!

Champstar

I'm having the same problem, but I cant seem to find where the camshaft position sensor exactly is located... 93 ls400