SCJ Throttle Body Issue

KushBandit

Member
Established Member
Joined
Aug 10, 2014
Messages
560
Location
California
So after checking for vacuum leaks, I think I narrowed down my surging idle issue with my Cobra Jet setup. My tuner isn't the quickest to respond to emails so I'm trying to figure it out.

Today, while I was getting on the freeway onramp, I go WOT and spin 2nd gear hard like usual. This time however, the car lost power and the wrench light popped up. I pull over and check the codes with my bluetooth odb2 app and got a P2112 code, which is telling me the throttle body was forced closed.

I clear the codes and restart the car, its able to drive and I get back on my way home. As I sit in a section of traffic, the car starts idling around 1200rpm. The throttle felt as if it was stuck open.

Lastly, the throttle body gets too hot to touch. I'm thinking the servo is burned out but I'm curious if anyone else has had similar issues.

Edit: just went for a late night cruise to see how it runs after inspecting the throttle body actuator and spring assembly. Everything is fine. I did an idle relearn and that seems to have helped the idle a bit. No codes and the throttle didn't force shut like it did earlier in the day.

The throttle does seem to stay open around 1300rpm when decelarating, but I wonder if that's in the tune. I have a doct. appt. later today, so I'll update how it runs when I drive.
 
Last edited:

mastwolf

4800fps = Mach1 in h2o
Established Member
Joined
Feb 18, 2005
Messages
1,396
Location
FL/Texas
With the CJ, alot of the DBW tables along with torque tables need to be Calibrated. Only a few people do this correctly.
 

1 Alibi 2

Veteran,...retired Navy !
Established Member
SVTP OG 4 Life
Joined
Aug 27, 2011
Messages
6,873
Location
Hackettstown, N.J.
There have been several threads on this site about this throttle body & surging issues, usually turns out to be a tune problem.
Some tuners don't like, ( can't ), tune them.
Couple of years ago, there was a batch from Accufab that had defective blades.
..............It's a good T/B, when tuned correctly.
.

.

.
 
Last edited:

KushBandit

Member
Established Member
Joined
Aug 10, 2014
Messages
560
Location
California
Well I drove the car today and it felt pretty good. The only "hiccup" I had was when I was pulling into my neighborhood and my throttle seemed to stay open around 1200rpm again, with it revving up to 1400rpm after placing it in park before shutting it down in my driveway.

I'm starting to think its a tune issue as you guys have stated. I'm running the baseline tune for the CJ setup and haven't gotten a revision yet, so the tune may very well be the issue. The thing that makes me question the TB is that it seems to run fine when its cold out, but sitting in hot traffic makes it whack out.

I appreciate the feedback guys.

Nice cold weather today with the rain, we certainly need the water here in California lol.

Alibi, that's a sweet looking engine. Who painted the throttle body logo, its looks great.
 
Last edited:

KushBandit

Member
Established Member
Joined
Aug 10, 2014
Messages
560
Location
California
As stated your tuning is fubarred. Even my base maps never did what yours is doing.

That's what I'm leaning towards now. Hopefully Mike Rousch gets me a tune revision asap, I'm confident he'll get it squared away if it's in the tune. I understand hes a one man shop so I'm not upset that he lags a bit with emails, but having an unreliable car I just put together sucks.

If not, I'll be contacting either Shaun at AED or Lund Racing.
 
Last edited:

Bullitt 3309

Member
Established Member
Joined
Feb 26, 2012
Messages
482
Location
San Antonio, Texas
I had some issues with the first CJ Mono Blade I bought here used. Did the same thing to me. No tuning helped, I replaced both the TPS sensor and actuator motor. Turns out the TB was a Summit Racing return being sold as "used" no issues. Thankfully AED was able to help me figure that part out... I bought a NEW one from TASCA and no issues since... I can't see Mike Rousch having a CJ tuning issue. If you got it used PM me for details. As far a tuning goes I recently swapped from AED to Lund since I wanted the nGauge. Both tunes drove well, but I have to give the nod to Lund as the throttle response is 100% better.
 

KushBandit

Member
Established Member
Joined
Aug 10, 2014
Messages
560
Location
California
Well, I solved the issue. Not sure what it was exactly, but I cleaned my MAF sensor and disassembled the TB, greased the gears then reassembled the spring assembly to 220 degrees as it comes from the factory. I'm leaning towards the MAF being the problem.

So far after driving roughly 60 miles, I have no issues what so ever. Nothing I try will induce the problem. With that said, Mike Rousch has no problem tuning the Monoblade throttle body. Car drives excellent now. I'd put his tunes up against AED or Lund when considering a Cobra Jet setup.
 

Users who are viewing this thread



Top