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Discussion Starter #1
The other day I was driving around and all of the sudden my rpms jumped from 1.5k to 2.3-4k I figured I was low on tranny fluid and I was but not by much so I topped it off using a gal jug I have not the whole thing just about a quart and a half. Well then it was working fine the rest of then night but the next day I did it again only it was several times that time I checked the tranny fluid again and it was a little high maybe a half quart. Oh yeah I have a 90 Eddie bauer I believe has a c6 trans. So I'm thinking I either need to get a new tranny or its the clutch plate. Please enlighten me great bronco gurus
 

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yo d,
It could be an electrical (sensor) problem, so do a self test for Codes and post results here;
a Self Test by Steve83
run it around to heat the engine up and shift thru all gears incl Reverse.
then; turn off all accesories/lights, etc.

Do KOEO portion first
For Key On Engine Running (KOER) portion, the engine has to be @ normal operating temp.

Post any codes found here or look em up in my broncolinks.com site.
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A Pure GUESS is da Idle Air Control (IAC) sensor;

Overview & Testing; "First let me say this little thing has many names. But they all talk about the same item under the hood. Here all the names I’ve had the torture of learning throughout the years: Idle Air Bypass •Idle Air Control •Idle Speed Control •Throttle Bypass Air •Idle Bypass •Inlet Air Controller •Inlet Air Bypass •Intake Air Bypass •Intake Air Control..."
Source: by Ryan M (Fireguy50) at http://fordfuelinjection.com/index.php?p=39

Hitachi Idle Air Control Valve Recommended Cleaning Procedure
Source: by Steve83 (Steve, That dirty old truck) at http://www.supermotors.net/vehicles/registry/media/231296
or TPS
 

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If it's doing this while you are driving with no change in speed (or lack of acceleration)... I might suggest checking/changing your transmission filter. Sometimes these can allow some air in if they don't seal properly, and well, if you get air in and it will seem to slip. The test is to overfill your tranny "a bit" and if it doesn't slip, then that is most likely what it is - the filter. The bad is that you can leak tranny fluid out the dipstick seal if that ain't sealing too well. A LOT cheaper to replace the filter than to replace the tranny. Filter kits are around $9 to $12 for a C6.
 

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Discussion Starter #5
Ok thanks ill pull the codes and test the filter ill let you guys know the results after work
 

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Discussion Starter #6
Well I pulled the codes and I got back 67 neutral drive switch 13 rpm out of specification during normal idle ego signal lean I did the filter and it did seem do run smoother for a little
 

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yo,
ok
DTC 67; "..One poss is that the NSS (or also called the MLPS) was ok...or connector was/is bad/corroded; or AC was left on, or transmission was in gear during the Self Test If you have AC, was it on do\uring KOER?
 

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ok

Do you think you have a Vacuum leak(s)?
Vacuum Leak Test; "...On idling engine...Check for vacuum leaks using a mechanic's stethoscope with the probe removed, or a ~3' garden hose. Don't spray flammables on a running engine. Also check the brake booster, the 2ndry air (coffee can) & HVAC vacuum reservoirs around intake manifold; and maybe under dash behind control panel vac line area..." ...(BEWARE OF BELTS/PULLEYS, FAN AND HOT ENGINE
Source: by miesk5 & Steve83

Next
Let's look @ the TPS;
Test, Operational Description & Parameters
Source: by Ryan M (Fireguy50) at fordfuelinjection.com

I have more TPS Test/info Links in my site under Electrical, Sensors

Idle Air Control (IAC) sensor. Also look isnide throttle body port for gunk build-up. Go thru the tests prev posted. Esp Ryan's; he wrote; "...Go under the hood, and disconnect the electrical connector to the IAB. If the engine begins to stubble or stalls the IAB is functional and does not need to be repaired. If the engine idle does not change you should remove the IAB for inspection..."

And Steve's see if you have that yellow sticker.. do not clean or whatever on it..


Idle Air Control (IAC) Sludge; Poor Idle TSB 91-25-07 for 85-92 Bronco & F Series & many others; "...Hard cold starts, hesitation and stalls on initial start-up or during idle or decel may be caused by sludge in the throttle body and/or idle by-pass valve. Sludge deposits or oil film on the throttle body bore and plate or the idle air by-pass valve may cause one or more of the following conditions. Hard Cold Start, Stall On Initial Start-Up, Stall During Idle, Stall During Decel, Rough Idle, Rolling Idle, Hesitation During Acceleration. A new idle air by-pass service kit (F2PZ-9F939-A) is now available for service use to correct sludge contamination concerns of the throttle bore and plate only. It eliminates the need to clean the majority of past model throttle body applications. Cleaning is not required on sludge tolerant throttle body designs released for 1991 and newer model years..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at http://www.supermotors.net/registry/media/724437
 

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Discussion Starter #10
Iac is good and gunk free and it appears that I have no vac leaks
 

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Discussion Starter #11
Ok so today I really gunned it today to see what would happen and well the rpms would jump up about 1k at a time but I really wasn't getting any power out of it. When I got home I reved the engine while in park the rpms climbed perfectly and sounded beautiful and very health
 

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Discussion Starter #12
Ok driving my bronco today and it seemed like it didn't want to shift out of 1st. I was shifting manual for a bit then after that it was shifting but was waiting till about 3.3 k rpms its it time for a trans or clutch plate?
 

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That sure sounded like what our 1990 Bronco 302/AOD did. 30 miles north of Alamosa, Colorado. Stopped at a flashing red light, started out and never came out of first gear. Fist gear all the way to Alamosa. The tranny shop said a couple bands were about gone. I'm not a tranny expert, but an tranny inspection should be something on your very short list of things to do. Might be other suggestions chiming in.
 

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Discussion Starter #14
Ok cool ill check it out either today if I can get out there before dark or tomorrow
 
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