95 Idle Issue

rickbtbird

Registered User
Last summer I purchased a 95 and drove it back from Florida. On the way, I split a motor mount on the passenger side and blew an alternator some where in Maryland, on a Sunday. That alternator was a $500.00 bill from Sears I'll never forget. I limped back to Connecticut and parked it.

Last Fall I decided to tear into it and do the all the mounts, both engine and tranny. I got those done in my spare time and few broken knuckles and bolts and a couple of spare parts from some nice SCCoA members. THANKS!

Along the way football season and winter set in. In the Spring I became semi disabled temporally. It's took me until late summer to get totally back to where I can get under a car.

In the spring, my 90 start acting up. It had this intermittent high idle problem. I knew it was the IAC so I swapped it out with the one from the 95. That worked perfectly.

I finally got the bugger reassembled this weekend. It's been almost a year since I turned my first bolt on this thing. Along the way I put in new plugs, wires, coil, IAC, and some under drive pulley, a few new gaskets and 5% jackshaft. I went to install the new SPC upper exhaust and found the passenger side doesn't fit. I ended up putting on the old one for now until I can get Bill on the phone.

So I get everything reassembled and slap on the EEC reader and I pull code 558 which tells me my EGR pressure regulator has no voltage. Ok crap I'm tired so I go to bed. Sunday morning I search for about an hour for the connection and the unit and it like trying to find a needle in a haystack. I search the SCCoA for "EGR pressure regulator" and don't you know it someone posted the location of the regulator, THANKS AGAIN! Its right where they said it was. The wires were hanging above it with two exposed female connections off the main wire harness. So I stick my hand down in back of the motor and something hits the ground sounding like plastic. It's the connector! So now I have a dilemma, which wire goes in which hole on the connector.. :confused:! Well it's got to be either one way or the other, so I attach the wires and rescan for code and it comes up all ones ;), I'm good to go.

It starts right up and the idle is fine, everything is looking good. I tighten up a radiator hose and drive it off the ramps. First stop in the Gas Station and fill up with 93. Done, I chirp the tires exiting the gas station and run the rpm’s up a bit until I hit the high way and engage the cruse control. Everything’s running like a top. No more thumping of the motor from the broken motor mount and my shifter doesn’t chatter anymore either. God bless the new mount kit.

So I pull off and head down the off ramp and a problem crops up that I don’t remember happening prior to the tear down. My idle hangs around 1.8k for about 15 seconds and the gradually goes down to 1.2 and then to around 1k. :mad:. The IAC is brand new out of the box from MotorCraft. It has the original part number on it that my junky old ones had.

Now I’m thinking about swapping the IAC out between the 90 and the 95 and see what happens next.
 
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I would say Iac or theres a chance your throttle cable is hanging up from sitting may have gotten rusty on the inside mine did and hung open the car revved to 3k rpms kinda sucked change the IAC 1st then get someone to help ya test the throttle cable have'em step on it with the car off while you see if it hangs...my sisters lumina has it happen because the pedal got hung up on the floor mat....go figure it was a chevy...:rolleyes:
 
I would say Iac or theres a chance your throttle cable is hanging up from sitting may have gotten rusty on the inside mine did and hung open the car revved to 3k rpms kinda sucked change the IAC 1st then get someone to help ya test the throttle cable have'em step on it with the car off while you see if it hangs...my sisters lumina has it happen because the pedal got hung up on the floor mat....go figure it was a chevy...:rolleyes:

No it's not the cable for sure. I'm starting to think it might be the TPS because after about 10 seconds the idle drops to almost normal.
 
Check your cables..Miller was having that same issues swearing up and down it was anything but the cable....It was the cable..Check the cruise control cabel as well
 
It's the IAC for sure. I unplugged it and the car idles perfectly. It's brand new out of the box from MotorCraft.
 
It's beginning to look like the 89-93 and 94-95 have two different part numbers for the IAC and crap I only got ones for the 90, MotorCraft p/n:CX-1826. It starting to look like the 94-95 uses the MotorCraft CX-1842 but I'm not 100% sure right now as I'm getting conflecting information off the web. What the hell $80.00 here and $95.00 there. Good thing I got both a 90 and 95 bird.
 
i had same exact problem.. also when I'd powerbreak, it would get stuck at 2k and my innocent 2 second burnout at a traffic light, turned into 20 second burnouts with my foot off the gas until the light went green. I saw i had router the crusecontrol cable like crap and along the fenderwall on driver side, it was looped all over. I ziptied that up, problem solved. also maybe your IAC screw is open to much, have you tryed messin with the TB yet ?
 
Yes check the IAC screw on the TB. Screw it in till it seats and remember how many turns out it was incase you have to go back to the original setting. But seat it and then turn it out no more than 1 turn. Ira R. just had this problem on his 5 speed that we fixed with the screw. Think i turned his out 3/4 of a turn. It was originally at 1 1/4.
 
Yes check the IAC screw on the TB. Screw it in till it seats and remember how many turns out it was incase you have to go back to the original setting. But seat it and then turn it out no more than 1 turn. Ira R. just had this problem on his 5 speed that we fixed with the screw. Think i turned his out 3/4 of a turn. It was originally at 1 1/4.

Geeze, that something I didn't know. Thanks for the tip, it worked perfectly. Can now idles down like it's suppose to. I'll have to wait until morning before I can get it to idle cold.
 
Here's a pic where the adjustment is for future references.
Mine took about 1/2 turn from bottem to get it to idle down correctly.
 

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Idle Adjustment

This morning I started the car up cold. The idle ran up to around 2k for a brief 3 second period and then down to 1.5k and 10 seconds later ran down to 1k. Once the engine was warm it went to it's expected normal 700 RPMs.

I've been trying to find a reference in any of the four shop manuals I have on hand regarding the screw adjustment. I haven't found anything yet. All I know is this adjustment appeared to have worked and resolve the high idle problem. :) Who knew?
 
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