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87 420SEL Wont Start

2564 Views 5 Replies 5 Participants Last post by  Benzical
Need some help.
For some time the car has idled rough.
Recently getting very hard to start.
When it does start, it dies as soon as it goes into gear, recranks pretty easy, keep revs up and I can get down the road.
Checked cold start valve, it sprays.
By-pass air valve, cleaned, seems to function. Disconnect and idle goes up to 2000rpm.
To get home last Friday had to disconnect it to get it to crank and got home.
Due to other projects, it sat till Mon morning and it won't start.
I can smell gas after cranking on it a bit, also poored gas down the throat, no change.
It seems to crank over faster, but only seems to hit on a couple of cylinders when I let off the key.
Checked for spark, pulled plug and grounded it, spark seemed good.
Tried to adjust timing with someone cranking, didn't find a point where it seemed like it was firing better, rotated about 5deg back and forth.
Anyway, I think it may have jumped timing. (194K miles)
Is there an easy way to check?
What jumps first, left bank, right bank or distributor?
Also, I can hear the fuel pump running when I am trying to crank it.
Spark, check.
Gas, I think so.
Air, check.
Timing, don't know.
Compression, I think so, no reason for it to change suddenly.
1 - 1 of 6 Posts
You didnt' adjust timing, you just adjusted where the rotor contacts the cap..

If you jumped timing you wouldn't be cranking, you'd be deciding if you were going to spend 4-5K to fix it.

Get that chain and tensioner changed.

I'm wondering if your CPS is still functioning properly. I know in the manual there is a procedure on how to test it.

You can hear if your compression went to hell in a cylinder or two when you turn the car over, it would sound a little dead/less crisp.

1 - 1 of 6 Posts
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