Modded Throttle Body - High Idle - Codes 122,335,558

[Explorin'VA]

I just modified the throttle body on my 94 as seen in this thread:
http://www.explorerforum.com/forums/showthread.php?t=185223

When I took the throttle body out, I accidentally snapped the elbow to the CANP vacuum line that attaches to the bottom of the throttle body. What's the purpose of this line?

I followed the guide and went to put the throttle body back in. When I started the engine the check engine light was on and it idled at just under 2000. When in gear, it idles at 1000. The normal idle is between 5-600. Any help on how to get the normal idle speed back?

Codes 122, 335, and 558.

 

[Explorin'VA]

I replaced the broken elbow in the vacuum line and cleaned my TPS sensor really well, but I'm still having erratic idle and a check engine light. Basically I start it up, idle speed settles at 1000, then rises up to about 2000, and that's when the check engine light comes on. When in gear it coasts at a steady 1000rpms, which isn't too bad. I'm just annoyed when it idles around 2 grand.

I'm thinking about just going back to the stock throttle body. I haven't checked voltage from the TPS sensor or PCM. Is the TPS sensor and PCM not cooperating because of the modified throttle body? I'd like to hear if anyone else has had this problem.

 

[swshawaii]

Installed a modified Zabteck throttle body on my SOHC and broke the spring on the TPS installing it wrong out of two possible ways . Threw a p0122 and the ST was undrivable with bucking shifts and high idle surges like yours. I'd say
test your TPS first. Good luck.

http://www.mysporttrac.com/shared/msgboard9e.asp?BOARDNAME=MSG&VIEW=1239396

 

[jd4242]

Sounds like you have a vac leak somewhere or didnt hook the egr back up right.. In the closed position nothing should be different. May have a leak around the shaft..

 

[IAmTodd]

Installed a modified Zabteck throttle body on my SOHC and broke the spring on the TPS installing it wrong out of two possible ways . Threw a p0122 and the ST was undrivable with bucking shifts and high idle surges like yours. I'd say
test your TPS first. Good luck.

The 122 is for the TPS. When I did the mod on mine I left the TPS screwed in and spun it around once and broke it. $25 less learned. Pop a new one in and you should clear at least that. The other codes could be in memory from the previous vac leak.

 

[Explorin'VA]

The 122 is for the TPS. When I did the mod on mine I left the TPS screwed in and spun it around once and broke it. $25 less learned. Pop a new one in and you should clear at least that. The other codes could be in memory from the previous vac leak.

That's what I was thinking. I left the TPS on during the mod and was pretty certain I damaged it because dust and grease got onto the prongs, not to mention I probably jolted it a couple of times. I ordered a new one last week from Rockauto and according to USPS tracking it will be at my house today. Idle surges and huge decrease in gas mileage all point to the TPS being bad. Come to think of it I've had codes 335 and 558 since I got the truck. I replaced the elbow I snapped and reconnected the vac line, so I'm pretty sure a new TPS is the solution. Will let y'all know after I install the new one.

 

[IAmTodd]

One way to test for sure, disconnect the MAF. If it won't run the TPS for sure is the issue. It requires at least one of those two to run.

 

[Explorin'VA]

Put on the new TPS and it runs smoothly again. The two screws that held in the old one were hard to break free without stripping them, which I ended up doing. I used vice grips to take the top screw off, but didn't have enough room to get the bottom one, so I just took a sawzaw to the sensor and cut away the plastic until I could get an angle on the bottom screw with the vice grips. Then I bought some new bolts for the replacement sensor and coated the threads with anti seize.

Thanks for the help. Throttle response feels quicker after modding the TB and replacing the sensor.

 

[IAmTodd]

Do you remember what size bolts you used? I nearly stripped mine out removing them and would like to put actual bolts on before I have another problem.