Weird Idle

[JC]

I recently bought a 98 SHO with 88k miles on it. The cams are welded and has Magnaflow mufflers and a K&N intake. Within the past 2 weeks Ive had the all the fluids flushed/changed and new filters. Occasionally, maybe once out of every 20 startups, the idle will jump up and down and eventually bog out and shut the car off. Also, sometimes the idle will climb slowly while in park which forces me to turn the car off. I did a search and with what I found, it seems like I may need to get the upgraded TB. I will be going to the Ford dealership in the morning to see if they have it. Other than that, should I have anything else looked at? Heres a video of a weird idle jump I get usually around 50mph while cruising. The idle jumps to 2k and then drops again, repeatedly. Sometimes, at any speed, the idle drops and it feels like the car is making no power... as if the car cant decide which gear it wants to be in.

http://youtu.be/OB5rqkMlaUg

 

[newshofan]

Get the new Tb and that should fix your issue. You may not like the cost seems like they told me around 70 bucks at my dealer I worked at. I wound up getting a regular sensor and a new connector from oriellys and napa. Mines a 96 but mine did the same thing. Might check on the idle air control valve as well.

 

[JC]

The Ford dealership had no idea what I was talking about regarding the upgraded TB. Do you know the part number? I assume that same part number would work if I took it to Autozone or Oreillys right?

 

[stephen newberg]

I believe that you are looking at 2 different problems. Perhaps the TB will cure your difficulty with the idle climb or bog, though I suspect it is just as possible that the idle air control needs cleaning up. On the problem of the RPM jump while cruising, that is the torque converter slipping in and out due to a signal from the climate control system and it is normal. You can prevent it from happening by shifting the climate system into 'vent' or you can get someone to sell you a programming chip and have them program this particular somewhat irritating trait out.

pax, smn

 

[Mr Anonymous]

I have no idea where you got "upgraded TB", but on 98-99's high idle issues call for replacing the TPS wiring pigtail per TSB 00-3-5.

I also agree that you might have an IAC problem.

Please change your city in your profile to something not racist.

 

[JC]

The Ford dealership had no idea what I was talking about regarding the upgraded TB. Do you know the part number? I assume that same part number would work if I took it to Autozone or Oreillys right?

 

[JC]

Thanks for the replys.

I apologize if my city name has offended anybody. Its been like that for about 4 years now. Im on my phone at the moment so it will take me a few mins to navigate the forum to update it.

 

[calvin0325]

Due to the music I could not hear what it was doing.....but from what I was seeing I would guess you had the defrost or a/c on and like mentioned it was the t/c engauging and disengauging.....as mentioned you will notice it doesn't do it with the climate control on vent...as mentioned above..... a new IAC (motorcraft) and cleaaning the MAF and throttle body should cure your problems .....if not check into the TSB .....but the IAC and cleaninng fixed my idle problems that I had on my 99.

 

[Mr Anonymous]

The Ford dealership had no idea what I was talking about regarding the upgraded TB.

That's because there is no such thing.

 

[stephen newberg]

That's because there is no such thing.

I think he was talking the TSB about the TPS wiring pigtail. That was my assumption, anyway.

pax, smn

 

[JC]

I think he was talking the TSB about the TPS wiring pigtail. That was my assumption, anyway.

pax, smn

Yeah. :/ Typo.

 

[JC]

They will be doing the TPS wiring pigtail in 2 days when it comes in (ordered, has to arrive from KS).

Thanks!