HT4100 4.1, 4.5, 4.9 Discussion, '88 DeVille EXTREME ISC problems in Cadillac Engine Technical Discussion; Hey everyone. I'm not sure if you all read my post in the FWD forum that my '89 Fleetwood was ...
Hey everyone. I'm not sure if you all read my post in the FWD forum that my '89 Fleetwood was destroyed last weekend. I'm going to buy an '88 Sedan DeVille as it's replacement with only one issue: the E30 code. My Fleetwood had the code intermittently and would idle high when first started and went to normal about two seconds later every time. This DeVille idles in the correct RPM range, but the idle is VERY rough and sporadic. The engine is jerks but accelerates beautifully. The E30 code comes up every time the car is started, but not always right after starting. What I was wondering is if there was any issue besides the ISC motor (i.e. spark plugs, etc.). The current owner has claimed that a lot of parts have been replaced on it and according to my thorough inspection, they have been. Any advice to this novice would be greatly appreciated!
I just heard from the current owner of the car that the ISC motor was replaced this year. Apparently, the technician that installed it did not adjust it. Is it true that I need a 12V power supply to be able to do such?
It's not too bad of a job. You have to pull the distributor (remove the hold down bolt and clamp), and pull straight up. Then, you remove the gear by punching out a small pin with a dull punch at the end of the distributor.
When I removed the distributor, I took several pictures with my camera of the rotor position, then made sure that it lined up when I reinstalled it.
If you have a timing light, jumped the 2 pins on the ALDL connector and check your timing. If the timing mark dances around a lot, this may be your problem.