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Discussion Starter · #1 ·
heres my data that i got from my scan tool..
o2 voltage .48 to .52
o2 cross counts .57 to 70
tps .46
maf 7
Lv8 46 to 50
iac 46
i also check vacuum which is 10 at park and 10 in drive..

still my car boggs and hesiates at idle how do these numbers look and thing else to look for..anything that would cause a bad idle or hesiation...when i drive my gn it boggs and hesiates when i keep my foot on the throttle when iam crusing about 45 to 50 mph...and sometimes it boggs and it seems like it wants to die...any other suggestions that can help ? thanks
 

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If you have a stock cam, the vacuum should be around 15-17 in Park.

I would start looking for a vacuum leak
 

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Iac counts too high.

Run a leak down test, and a compression test as well. Oh, was this in park or drive?

how are the plugs?
 

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Discussion Starter · #4 ·
ok if my iac counts are to high what are the specs of the iac and what should they be ? how can i get the iac counts lower ? the vacuum test i did was at park and in drive both read 10 on the vacuum gauge..does this tell me that i have a vacuum leak somewhere ?
i looked for leaks i found no broken hoses, but my vacuum block that sits on the top of the throttle body is still stock..should i replaced that? could that be my problem..i check it i found no leaks and it doesn't looked crack or warp also my plugs are good they are brand new ac delco 43 gap at 0.35..any other suggestions ? thanks
 

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IAC counts are high, TPS is borderline part-throttle, 02 sweep isnt enuf, MAF at 7 is too high for idle. That'd be more like 1300ish RPM.

This is one reason I dont care for scanmaster as a scan tool. It is good if you know what you're looking at, but to ask for help giving numbers like that is pointless. What are the numbers doing when it acts up? What are the numbers under different op modes? Do you have a friend with at least turbolink who can capture the car running so you can send that file around for people to look at? How 'bout diacom? I suggest if you are relativly serious about keeping your car and performing driveability diagnostics on it, you at LEAST buy turbolink. If your REALLLLLY serious, go with direct scan.

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Jim Testa
1986 Regal T-Type
Stock block, Turbomotion ported heads, PTE 210 roller cam, GNT ported intake, PTE Plenum, 70mm TB, PTE FM IC, MSD 50's, TE61, TPS-TEC, JT Chip, JT 200R4, Vigilante 2800 LU convertor, JT Boxed lower arms, working on girlde....
 

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Amen, Jim
 

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start by finding the vacuum problem, i'm sure once that is taken care of the other issues will start being more manageable. some guys use propane to find vacuum leaks, i prefer either starting fluid or carb cleaner. if youre gonna use one of those 2 make sure you do so before your motor gets up to temp, starting fluid on hot headers may be a baaaad thing. just spray each vacuum line connection and listen for a change in idle. when you hear the change you've found the leak.

good luck, aaron
86 GN
 

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Discussion Starter · #9 ·
i traced each vacuum line today and they are all fine..i think iam going to replace my stock vacuum block on top of the throttle body also if my maf is high at idle how do i bring it down to specs?
 

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idle screw on the TB, that is covered by a silver/grey cap, you adjust this, then reset the tps, the re adjust the IAC then the tps, until you got them both in the correct tolerances.

do this with the car warm... IE drive it around...
 

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I usually use a propane torch....unlit, of course.

Check the base of the doghouse, then around the bottom of the vacuum block...I doubt that you need to replace the vacuum block...
 

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wonder if it has jumped a tooth on the timing gear?
 
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