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...Of all the paths you take in life - make sure a few of them are dirt. -
Ok, got code 33. MAP sensor signal voltage too high (low vacuum) Truck seems peppy enough for a 4.3 if that has any bearing.Of all the paths you take in life - make sure a few of them are dirt.Comment
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GM OBD Trouble Code 33
MAP Sensor Circuit Error (Signal High Indicating Low Vacuum)
The ECM uses the Manifold Absolute Pressure (MAP) sensor as an indication of engine load. High voltage would indicate low engine vacuum and higher engine load. Low voltage would indicate high engine vacuum and lower engine load. The ECM uses the information from this sensor to help calculate fuel delivery and spark timing.
Fault Code Description- 33 - MAP sensor circuit error (signal high indicating low vacuum)
- Poor engine performance
- Engine running rich (too much fuel, black smoke from exhaust)
- GM MAP sensors do not commonly fail
- Due to erratic engine vacuum, other engine performance problems can cause a code 33 to set
Doing it all wrong since 1966Comment
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During the change from closed to open loop, does the ECM look for MAP sensor input?
In other words, could an incorrect value from that sensor cause the computer to change course and revert to the previous fuel map - causing what we term a "stutter"?
Of all the paths you take in life - make sure a few of them are dirt.Comment
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hard to tell from here - is the stutter a lean condition? I think I'd check all the other stuff - spark plugs, wires, cap first. I know that a shorted wire will throw a similar code. After that, you can test the MAP sensor http://troubleshootmyvehicle.com/gm/...e-map-sensor-1
the tl;dr is sure, it could - but I wouldn't start there because they are pretty robust.Doing it all wrong since 1966Comment
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Just to be clear.......I'm not the worried in the least on my truck. It runs fine, especially for a beater.
Just thought it would maybe help diagnosis your issue - since they are very similar ECMs.
My stutter is very infrequent after warmed up, but is very predictable during that first couple miles after a cold start. How would you describe yours?
Of all the paths you take in life - make sure a few of them are dirt.Comment
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how to describe? as an ignition issue
Not a lot has been happening - most of the major problems have been solved so I've been dealing with other, non-car stuff....
but first I complained about how I need to break down the sidewalls a bit... this is 3 psi
needed to add a light to the dash... which I did
and then while I was cleaning up a hole, tore the wire out of the light .... picture when I get its replacement
finally purchased a distributor wrench....
this is for my wife's jeep - which I would have worked on tonight had she not been out doing SAR stuff....
blanking Mr. gasket clamp.... chromed aluminum clamp - no wonder it wasn't holding. First it had too much material so it wouldn't clamp at all... then I ground it down and it wouldn't hold after a bit...
it is clamped now. I've solved my Staun problem (18 psi instead of 8 psi deflation) with the purchase of an ARB deflator (and I have spare needles) and I got a better hose for filling.... this weekend will be a good runDoing it all wrong since 1966Comment
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so the stutter was caused by the dizzy slipping out of time?? Had that issue with a Galaxie back in 86...Patrick & Tammy
- Long Haulin' 2008, 2009, 2010, 2011, 2012, 2014...Addicting isn't it...??Comment
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yep, because of a cheap, chinesium hold downDoing it all wrong since 1966Comment
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a good reminder to clean and inspect the mating surfaces as well... I've had these slip because the gasket was oil soaked or missing altogether...I've also roughed up the edges of the clamp for more bite...Patrick & Tammy
- Long Haulin' 2008, 2009, 2010, 2011, 2012, 2014...Addicting isn't it...??Comment
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steering issue is fixed. drove it tonight at it works very well. the fix was bracing the box and the panhard bar. It still has some throttle-induced understeer but since the fix would be making the panhard parallel with the axle - and the down side of that is increased bump-steer; I'll take the lesser of two evils. Especially since the lesser only happens noticeably when accelerating from a stop sign while turning (and right is worse then left).... time to get onto the next project and work on beating this thing like it owes me money. (thank you Finnegan for that quip).Doing it all wrong since 1966Comment
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There's another cure for the throttle steering - simply reduce the engine power!
That probably ain't gonna happen.....
DanComment
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No hablo "reduce power"Doing it all wrong since 1966Comment
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what a glorious day - got cut short because the alternator stopped working, but still.... it was a point and shoot day in the snow (meaning wherever I wanted to go.. no problem)
normally speaking, there's a frost line on the hills - not this time, so there wasn't the slog through the cascade cement...
got a little snow up its nose
then air up
then breakfast at the cafe - an all-you-can-eat.... I like all you can eat
Doing it all wrong since 1966Comment
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Looks like a wonderful day!
Sure beats mud, altho cold!
Bet it feels good to drive!Comment
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