4 + 3 Overdrive Question
Thread Starter
Safety Car
Joined: Feb 2000
Posts: 3,771
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From: MANDEVILLE, LA La
4 + 3 Overdrive Question
My 84' O.D. works fine except.......If I get to hwy speeds without really flooring it when not in O.D. it works great when I engage it and just cruise. Makes no differnce how fast you go once your in O.D. But....If I run it real fast to say 90 mph then engage the O.D. It feels like a bad engine miss.If I disengage it it runs fine Re-engage it it misses. then after a 20 30 seconds of this it smoothes out like nothing ever happened. Weird huh ? I thought it might be the O.D unit at first but after thinking about it I wonder if a sensor or even the ECM itself kinda freeks out after a hard run and cause a miss.remember. at 75 mph in O.D there's an awful lot of load on the engine just reving about 2,200 rpm or so. What do you think? any Ideas?
Team Owner
Joined: Mar 2000
Posts: 83,383
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From: Boston, MA
Ok so if you just cruise laxidasical up to speed and engage it, it is smooth. Yet if you are hammering it through the gears, and then engage it, it makes the car shudder? Hmm...
Now is this only if you are at full throttle and engage it. What if you run it up to 90, let off the gas, and THEN engage it? Are you using the clutch when engaging? You don't HAVE to, but lots of us do.
When was the last time the filter/fluid was changed?
Now is this only if you are at full throttle and engage it. What if you run it up to 90, let off the gas, and THEN engage it? Are you using the clutch when engaging? You don't HAVE to, but lots of us do.
When was the last time the filter/fluid was changed?
Thread Starter
Safety Car
Joined: Feb 2000
Posts: 3,771
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From: MANDEVILLE, LA La
Re: (scorp508)
That's correct...At 90... Put clutch in...Let it out Now just try to cruise at that speed or even take your foot off thr throttle completely..It still does it. Disengage O.D....Cruise in 4th for a while...Put back in O.D. it's then fine.
Go figure. BTW..I change the fluid every year or 10,000 K
Go figure. BTW..I change the fluid every year or 10,000 K
Thread Starter
Safety Car
Joined: Feb 2000
Posts: 3,771
Likes: 0
From: MANDEVILLE, LA La
Re: (scorp508)
Come to think of it....after it did it.. I never went to see if it would do it again, 2 times in a row..after blowing the carbon out so to speak. BTW..the engine has 198K on it. I thought using a quart of Mobil 1 every 3-4 hundred miles might have a bearing on it as well.Could , let's say, the O2 sensor be coated with an oil residue not allowing it to read the fuel mixture till the oil is burned off ?? I don't know...just throwing out ideas.
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Thread Starter
Safety Car
Joined: Feb 2000
Posts: 3,771
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From: MANDEVILLE, LA La
Re: (scorp508)
I'm really surprised though...I really don't see any smoke ...at least from the rear view mirror...I do see a puff once in a while when I first start it..valve guides a tad worn.Raeely...it runs so well I hate to dig into her...