Spyder High Idle, cant solve problem (Spyder Gs)

[epreski7]

98 Spyder Gs 4g64. Car will idle fine during cold start. After warmed up idle will be at 2000 in park and neutral with ac off, when I turn the ac on it'll idle at 1200 with occasional jumps to 1600. In any other gear it'll idle at about 1000 with ac off and 900 with ac on. TPS is currently reading 0% because if I set the cable to 10% it'll idle at 4000. Have replaced all the gaskets, swapped in 3 different throttle bodies with 3 different sets of sensors, new ram air intake yet problem persist no matter what I do. Tried spraying carb cleaner on hoses and gaskets during cold start but no jump in idle anywhere. Adjusting BISS screw doesn't affect idle at all. If anyone has any ideas please let me know

 

[Dcmojo817]

98 Spyder Gs 4g64. Car will idle fine during cold start. After warmed up idle will be at 2000 in park and neutral with ac off, when I turn the ac on it'll idle at 1200 with occasional jumps to 1600. In any other gear it'll idle at about 1000 with ac off and 900 with ac on. TPS is currently reading 0% because if I set the cable to 10% it'll idle at 4000. Have replaced all the gaskets, swapped in 3 different throttle bodies with 3 different sets of sensors, new ram air intake yet problem persist no matter what I do. Tried spraying carb cleaner on hoses and gaskets during cold start but no jump in idle anywhere. Adjusting BISS screw doesn't affect idle at all. If anyone has any ideas please let me know

Not sure if you’ve done it but have you checked the Idle Air Control Valve/Sensor? If so the I can’t help much but I can say my car does the same on occasion but I don’t really worry about it.

 

[pauleyman]

98 Spyder Gs 4g64. Car will idle fine during cold start. After warmed up idle will be at 2000 in park and neutral with ac off, when I turn the ac on it'll idle at 1200 with occasional jumps to 1600. In any other gear it'll idle at about 1000 with ac off and 900 with ac on. TPS is currently reading 0% because if I set the cable to 10% it'll idle at 4000. Have replaced all the gaskets, swapped in 3 different throttle bodies with 3 different sets of sensors, new ram air intake yet problem persist no matter what I do. Tried spraying carb cleaner on hoses and gaskets during cold start but no jump in idle anywhere. Adjusting BISS screw doesn't affect idle at all. If anyone has any ideas please let me know

You don't adjust TPS by adjusting the cable.
I'm assuming changing throttle bodies came with a different ISC. If that's the case and BISS does nothing I'd say you have a possible issue with ISC drivers in the ECU. Bad ISC can take the drivers out. I'd be curious what ecu says about closed throttle also as you should never idle above 1500 ever.

 

[jinscho]

Start off by negating everything you've already done to 'fix' this issue. Reset the SAS screw and make sure the throttle plate is closing properly. Once the SAS is adjusted, adjust the throttle cable bracket so there is no slack in the cable while at idle, just be sure you don't pull it too tight as to open the throttle valve unintentionally. With these adjusted back to normal, you've ruled out the throttle plate itself as the issue and can turn towards the sensors.

Adjusting the TPS properly requires a feeler gauge and multimeter, however I have also been able to adjust it with my pocket logger while viewing live data. It took quite a bit longer than using the proper procedure would have, but I still have yet to remember to buy a set of feeler gauges when I'm at Harbor Freight.

Once the TPS is adjusted, start the car and get it up to normal operating temps so you can set the BISS. Again, there's a proper way to do it utilizing a scan tool to ground the ISC stepper motor. However I was able to do it by simply unplugging the ISC after the car had warmed up, adjusting the BISS so the car idled around 750-800 rpm, and then plugging the ISC back in.

If this doesn't bring your idle back down to a normal level, you have bigger issues than the throttle body.

 

[chrysler kid]

Loosen the 2 throttle cable bolts on the intake manifold, then push down on the throttle body unit.

Make some extra slack in the line.

After that you can unscrew the throttle plate screw. But I will warn you it can cause other problems with the idle air control valve.

 

[epreski7]

You don't adjust TPS by adjusting the cable.
I'm assuming changing throttle bodies came with a different ISC. If that's the case and BISS does nothing I'd say you have a possible issue with ISC drivers in the ECU. Bad ISC can take the drivers out. I'd be curious what ecu says about closed throttle also as you should never idle above 1500 ever.

Adjusting just the sensor wouldn't get me the 10% I've seen recommended it'd stop at 3.8% on my logger. Yes different isc with each throttle body. Ill have to check my logger tomm see what the ecu has idle set at.

Start off by negating everything you've already done to 'fix' this issue. Reset the SAS screw and make sure the throttle plate is closing properly. Once the SAS is adjusted, adjust the throttle cable bracket so there is no slack in the cable while at idle, just be sure you don't pull it too tight as to open the throttle valve unintentionally. With these adjusted back to normal, you've ruled out the throttle plate itself as the issue and can turn towards the sensors.

Adjusting the TPS properly requires a feeler gauge and multimeter, however I have also been able to adjust it with my pocket logger while viewing live data. It took quite a bit longer than using the proper procedure would have, but I still have yet to remember to buy a set of feeler gauges when I'm at Harbor Freight.

Once the TPS is adjusted, start the car and get it up to normal operating temps so you can set the BISS. Again, there's a proper way to do it utilizing a scan tool to ground the ISC stepper motor. However I was able to do it by simply unplugging the ISC after the car had warmed up, adjusting the BISS so the car idled around 750-800 rpm, and then plugging the ISC back in.

If this doesn't bring your idle back down to a normal level, you have bigger issues than the throttle body.

BISS screw is already back in factory setting and already have the cable adjusted to that point. I tried adjusting it with the logger but with the throttle cable properly adjusted I cant get the tps to read more than 3.8% on the logger and I've seen on other post it should be around 10% at idle so not to sure what's going on there doing it on both tps sensors I have. I have the tps set to where it was before I started messing with it for now. Ill try those seconds steps you recommended tomm

 

[chrysler kid]

Adjusting just the sensor wouldn't get me the 10% I've seen recommended it'd stop at 3.8% on my logger. Yes different isc with each throttle body. Ill have to check my logger tomm see what the ecu has idle set at.

BISS screw is already back in factory setting and already have the cable adjusted to that point. I tried adjusting it with the logger but with the throttle cable properly adjusted I cant get the tps to read more than 3.8% on the logger and I've seen on other post it should be around 10% at idle so not to sure what's going on there doing it on both tps sensors I have. I have the tps set to where it was before I started messing with it for now. Ill try those seconds steps you recommended tomm

No, on a 2nd gen it should read 0% at idle. On a second gen the tps sensor has an open closed switch, and the tps sends a signal back to the ecu to indicate the tps is closed.

It needs to be zero percent at idle. Technically per the factory service manual a 2g 4g63 should be reading .0177 less than zero at idle based on tps calibration.

This should be the same for the 2.4 spyder

Do not adjust the throttle stop screw yet. Like I said it will for sure mess with idle air control calibration and can throw check engine lights

 

[jinscho]

No, on a 2nd gen it should read 0% at idle. On a second gen the tps sensor has an open closed switch, and the tps sends a signal back to the ecu to indicate the tps is closed.

It needs to be zero percent at idle. Technically per the factory service manual a 2g 4g63 should be reading .0177 less than zero at idle based on tps calibration.

This should be the same for the 2.4 spyder

Do not adjust the throttle stop screw yet. Like I said it will for sure mess with idle air control calibration and can throw check engine lights

All of this, minus the worry of adjusting the SAS. While it shouldn't be adjusted unnecessarily, there are steps laid out in the FSM for ensuring it is at the proper position.

From page 13A-265 in the FSM:

- loosen the two bolts securing the throttle cable to allow slack in the cable
- back out the fixed SAS lock nut
- turn the fixed SAS counterclockwise until the throttle plate is completely shut
- turn the fixed SAS clockwise until it makes contact with the throttle lever. From that point, turn the fixed SAS an additional 1 and 1/4 turn.
- while holding the SAS in place so it does not move, tighten down the lock nut
- adjust the tension of the throttle cable

 

[epreski7]

Managed to find the problem though still can't fix it. Hooked it up to a smoke leak detector and it poured out from the bottom of the intake manifold gasket on cylinder 1. Sure enough take it out and the piece of the gasket there's blown out. Changed it out and it's still leaking from there so thinking the intake manifolds warped or bad resurface by the machine shop