1987 Prelude high idle, timing off, failing emissions test.
Thread Starter
Joined: Jun 2006
Posts: 1
Likes: 0
From: Discovery Bay, CA, USA
1987 Prelude high idle, timing off, failing emissions test.
Got 1987 Prelude a few years ago from friend, ran great about 75k miles on it. Overheated one day and blew head gasket. Took head to shop and had redone. Bought Chilton manual and replaced head. Didn't have timing light, so I timed by ear. Car ran OK, a little low end pinging. Took to smog and failed. NOX emissions were like 3.5 times the maximum, the timing was off and the idle was high.
Strange, before the car had no problems passing smog. Before I went to the smog station, the car idled high about 1100, it would not lower with the idle screw. After driving 30 minutes to get to the smog station, the car wouldn't idle, so I had to adjust the idle screw up to keep it running but I made it too high, around 1000. Didn't know they checked that.
Went home and got a timing light, hooked it up. Disconnected the vacumn lines going to the vacumn advance. The book said remove the lines, plug them and them put them back on. Don't know how that is possible. So I put two small plugged lines on the vacumn advance and plugged the lines that went on it. Found the viewing window for the timing light but can't seem to get to any mark. I rotated the distributer all the way down and the idle slowed a bit, but can barely see a set of marks still to the left of the timing hole towards the engine. It looks like a plus or cross but I can't time to that mark since the timing advance module physically hits the pipe below stopping it from rotating to the bottom of the adjustment range. Manual does not describe the timing marks for that year. The car runs much better now, no pinging. Good power. Strange I don't have the range on the distributer to get to the marks, could the timing belt be off by a tooth? What could be holding my idle high, it is around 1100, instead of 800. I drove around block until warm and the idle still won't come done. Not sure what happened when I drove it to the station and the idle dropped but I wish I could duplicate it, need the idle to go done before I can properly time it, could this be why I can't get to the marks? I drove today and started to idle at 800 when cold, very soon the idle picked up to 1300.
I can take it back to the smog, free test for 15 days but the idle is still high and I think he will fail just that. Could the timing being off by so much cause the immisions to be that high? What mark should I be using?
Any help is greatly appreciated.
Thanks in advance.
Jeff
Strange, before the car had no problems passing smog. Before I went to the smog station, the car idled high about 1100, it would not lower with the idle screw. After driving 30 minutes to get to the smog station, the car wouldn't idle, so I had to adjust the idle screw up to keep it running but I made it too high, around 1000. Didn't know they checked that.
Went home and got a timing light, hooked it up. Disconnected the vacumn lines going to the vacumn advance. The book said remove the lines, plug them and them put them back on. Don't know how that is possible. So I put two small plugged lines on the vacumn advance and plugged the lines that went on it. Found the viewing window for the timing light but can't seem to get to any mark. I rotated the distributer all the way down and the idle slowed a bit, but can barely see a set of marks still to the left of the timing hole towards the engine. It looks like a plus or cross but I can't time to that mark since the timing advance module physically hits the pipe below stopping it from rotating to the bottom of the adjustment range. Manual does not describe the timing marks for that year. The car runs much better now, no pinging. Good power. Strange I don't have the range on the distributer to get to the marks, could the timing belt be off by a tooth? What could be holding my idle high, it is around 1100, instead of 800. I drove around block until warm and the idle still won't come done. Not sure what happened when I drove it to the station and the idle dropped but I wish I could duplicate it, need the idle to go done before I can properly time it, could this be why I can't get to the marks? I drove today and started to idle at 800 when cold, very soon the idle picked up to 1300.
I can take it back to the smog, free test for 15 days but the idle is still high and I think he will fail just that. Could the timing being off by so much cause the immisions to be that high? What mark should I be using?
Any help is greatly appreciated.
Thanks in advance.
Jeff
Thread
Thread Starter
Forum
Replies
Last Post
Andrew760
Honda Civic / Del Sol (1992 - 2000)
3
Jul 24, 2011 02:07 PM
