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Old 09-04-2012, 12:08 PM   #21
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OK, finally got back around to looking at this again. The snagging is for sure the throttle cable. If I disconnect the cable, I don't have any sticking. When the cable is connected, the throttle sticks and the gas pedal is free after I push the throttle.

I am going to order a new cable and see if that does the trick. Only concerns is that with a JRSC, the throttle cable is routed in a long loop past the throttle body and back around to the throttle cam. Hope replacing the cable makes is not stick, guess mine is jammed up.
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Old 09-04-2012, 12:13 PM   #22
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Since its the cable, fix your routing, either the cable is being pinch by something or you have too sharp of a bend somewhere.
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Old 09-04-2012, 01:23 PM   #23
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Since its the cable, fix your routing, either the cable is being pinch by something or you have too sharp of a bend somewhere.
Even with the throttle body end of the cable and pulled out as straight as possible, it's gritty and hard to pull the cable back and forth. I think its just got a ton of stuff in it or its frayed inside. Already ordered a replacement, going to see if that fixes it.
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Old 09-04-2012, 02:47 PM   #24
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Water lines are capped on the IACV. I have removed the air valve at the side of the intake manifold as well. This is all in conjunction with doing the coolant reroute and removing the front water outlet neck.
Like olderguy was hinting at...you may have to add a coolant line to your IAC. When cool, that circuit lets extra air thru raising idle until it warms up. In my experience, it will pass too much air (high idle) when you disconnect it from a coolant line. I had the same problem when I initially did my coolant reroute. Added the line now it's fine.

Or you can block off the passage with jbweld within the IAC itself.
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Old 09-04-2012, 03:39 PM   #25
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I have fixed my idle being high now, don't know if it's from some other bandaid fixes I have done but it's idling fine now.

The issue is that whenever I push the gas, the revs fly up very quickly and come down very slowly. From experimenting, I have traced it down to the throttle cable. Going to be putting it in this week, will report back on if that's the solution.
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Old 09-04-2012, 03:49 PM   #26
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The 1.6 TPS is either idle or not idle (or is it WOT or not WOT?).
Late to the party, but some clarification:

The M/T 1.6 TPS has three positions: Idle, WOT, and somewhere in between. In EE parlance, it's a double-throw switch with center-off. One contact is closed to ground when at idle, the other contact is closed to ground at WOT, and neither contact is closed when the throttle is at some position which is neither idle nor WOT. (To confound matters slightly, the A/T 1.6 and '94-'97 TPSes have both an analog potentiometer and a switch which is closed when at idle.)

Regardless, a 1.6 engine with a megasquirt is fully capable of idling normally even without a "proper" TPS.
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Old 09-04-2012, 04:06 PM   #27
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You can also get rid of that dashpot to see if that helps any.
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Old 09-18-2012, 03:09 AM   #28
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So I finally got a chance to put in my new throttle cable from Rosenthal and it did the trick. Don't know if the old cable was crushed, gunked up or whatever. Either way, solved that problem. Revs drop great.

BUT think I found a new issue. Seems like tuning but idk.

When driving the car around tonight it would intermittently switch between driving fine to loosing seemingly all power in every gear at various speeds. Also it wouldn't idle in this "mode" either. Felt kind of like a misfire or pulling all the timing from the motor, just no power whatsoever.

Couple of times I pulled over, turned the car off and waited a minute. After some more starting, dying out, running poorly, it would "reset" itself and run absolutely perfectly.

Really weird that the condition would go back and forth like that, as to why I'm thinking something with tuning. Like it's bouncing into a cell that's messed up or something.

Making this post on my phone so it's difficult, will post a more coherent description tomorrow morning on here and will be giving my tuner a call as well.

Any ideas are appreciated.
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Old 09-18-2012, 10:10 AM   #29
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If you are running a one wire O2 sensor a bad connection or ground will open and the ECU will go to adding too much fuel while you are in closed loop(under 4000 rpm)
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Old 09-18-2012, 11:01 AM   #30
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If you are running a one wire O2 sensor a bad connection or ground will open and the ECU will go to adding too much fuel while you are in closed loop(under 4000 rpm)
Will have to check this out. Could I tell if this is the case based on AFR readouts on my gauge? Should it go rich/lean?

Drove the car in this morning to work, did the same kind of behavior. I would come to a stop at idle and it would be great for about 20-30 seconds, then instantly switch to idling low/rough and having no power (hard to rev). Wouldn't do it every time I came to a stop but at least 50% of the time.

Also when cruising at various speeds (30 in 4th, 50 in 4th, 25 in 3rd --- Just ones I noticed) it was switch from running fine to instantly running like crap with no power (hard to rev).
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Old 09-18-2012, 04:06 PM   #31
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Other problem that can look like this is a bad AFM.
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Old 09-19-2012, 11:20 AM   #32
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Other problem that can look like this is a bad AFM.
Don't have a AFM anymore. But I think I figured out the problem! Checked 02 wiring after your suggestion and found that I had an uninsulated spade connector in the wiring that I suspect was grounding the O2 signal to the ECU. Covered with tape and has been flawless for (2) 30 minute drives so far!! Think this was my issue.

Now the car is ready for the track this weekend. Thanks for all the help guys.
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