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Earlier distributor in 88 Wagon?


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11 replies to this topic

#1 greenacarina

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Posted 30 December 2008 - 07:10 PM

So, my SPFI wagon has this horrible hesitation under load....like almost undriveable. Can't find the info in any of my manuals on how the advance works (electronic, yes....but is there some vacuum sensor involved? how does it compensate for load?). Anywho, I was thinking of plopping in a distributor from an '85 that has the vacuum advance. Good idea? Bad idea? Should I be focusing my attention on something else?
Thanks!
Chris

#2 Skip

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Posted 30 December 2008 - 09:09 PM

I moved you post for better coverage

The distributor in your SPFI car is a
CAS - Crank Angle Sensor
insides shown here
Posted Image
The 85 has a more or less conventional electronic
dist.
completely different.

Have you changed your fuel filter lately?

#3 kayakertom

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Posted 31 December 2008 - 02:06 AM

Another possibility is the air mass sensor located by your air filter.

#4 greenacarina

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Posted 05 March 2009 - 03:57 PM

OK, got out today in the currently tolerable weather and played with this thing some more. Tested every aspect of the FI system to rule that stuff out of the euqation. Air mass meter is within specs, fuel pressure is correct while running and sitting for 10 minutes (fuel filter is new), throttle switch is adjusted correctly. So, the symptoms that I am dealing with- car starts and idles fine, acceleration is a bit sluggish when rolling gently into the throttle. Falls flat on it's face and backfires under hard acceleration and under load. Ignition timing is set to factory spec and appears to advance when using a timing light in the driveway. I am still totally unclear how the timing advance is controlled (ECU???) and how load is sensed (normally manifold or ported vacuum on most cars, but apparently not this one). Any insight??? The ol' Haynes book is maginal at best.

Chris

#5 greenacarina

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Posted 05 March 2009 - 04:00 PM

Sorry, should be "equation" and "marginal"

ALSO- Is my notion of putting an earlier vacuum-advance distributor (from an '85) in my car ill-advised?

Thanks.
Chris




OK, got out today in the currently tolerable weather and played with this thing some more. Tested every aspect of the FI system to rule that stuff out of the euqation. Air mass meter is within specs, fuel pressure is correct while running and sitting for 10 minutes (fuel filter is new), throttle switch is adjusted correctly. So, the symptoms that I am dealing with- car starts and idles fine, acceleration is a bit sluggish when rolling gently into the throttle. Falls flat on it's face and backfires under hard acceleration and under load. Ignition timing is set to factory spec and appears to advance when using a timing light in the driveway. I am still totally unclear how the timing advance is controlled (ECU???) and how load is sensed (normally manifold or ported vacuum on most cars, but apparently not this one). Any insight??? The ol' Haynes book is maginal at best.

Chris



#6 naru

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Posted 05 March 2009 - 05:22 PM

Your other disty won`t work.

ECU calculates required advance from TPS and airflow meter inputs.

Suggest you measure fuel pressure under load when the problem occurs.

#7 greenacarina

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Posted 05 March 2009 - 07:31 PM

Your other disty won`t work.

ECU calculates required advance from TPS and airflow meter inputs.

Suggest you measure fuel pressure under load when the problem occurs.


OK, will give that a go.
Thanks.
Chris

#8 ThirdEyeHatch

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Posted 05 March 2009 - 08:12 PM

Maybe a clogged cat?

#9 RMVR53

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Posted 06 March 2009 - 11:50 PM

Chris

you should check out the thread --- EA82 looses all power ---. You just might find a similarity/solution to your situation

Bill

#10 The Dude Abides

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Posted 07 March 2009 - 02:32 AM

What about vacume hoses fellas

#11 GeneralDisorder

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Posted 07 March 2009 - 03:17 AM

Probably a bad TPS. Check it through the sweep with a DMM - might have bad spots in it.

GD

#12 greenacarina

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Posted 13 March 2009 - 02:52 PM

Problem solved!!! It was a crappy fuel pump. This was certainly a good exercise in getting familiar with the injection system, however. Now on to more mundane things- timing belts, oil pump seal, exhaust studs...the usual suspects! :)

Chris




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