solomon7
NAXJA Forum User
- Location
- Portland OR
So here's what's going on. I have details and then a few questions and figured I'd merge it in to one. I hope ya'll can help. I'm goin' nuts over this!
96, 4 liter, 150km , AW4, NP231
The rig has been studdering on the highway randomly and at idle. On the highway it almost seems like it's missing but the rpms don't drop. The RPM bounces quite a bit at idle in gear from 800 to 1500 sometimes. I got 2 code 43s on the obd2 when it bucked really bad at a hot start, took it to the shop , they scanned it and came upwith a misfire in #3, nothing else.
I replaced plugs (old #3 plug lookes liek the others fyi) and wires and it idles better and has a bit more power, but the studdering is still there randomly, sometimes on a cold start then fine at speed, sometimes on a hot start only then fine at speed, sometimes hot or cold and at speed .
When I come to a stop, often it idles bouncing between 1100 and 750. THis is not a constant thing though. Sometimes it's fine. Today was the worst. It started fine warmed up fine and drove fine for about 10 minutes then the bucking at speed and crappy unstable idle happened coasting to a stop and idling in D. RPMs wer going all over between 8 and 1200. I shifted at the stop to N and In Neutral it seemed fine though........???? Tranny shifts great and is strong fyi.
On a side note It also doesn't always want to drop when I let my foot off at highway speeds till I tap the brake. This symptom sounded like TPS to me
so I just replaced the TPS with a BWD/Borg Warner (please lmk if I got the wrong brand!) a few minutes ago and now when I rev it and let off it "sticks" around 1100 unless I pull up a bit on the throttle lever on the body. Once I tapped the IACV a couple times and it dropped to normal. Could the IAC be crapping out as well? I find it strange that when I changed the TPS this new sticky high idle thing arose. Faulty TPS ? When it went on I did have to put it on at a slight angle to get it to align but I assume that's just preloading right, or is it faulty? I need to know so I can return it before it's too late. There's a small screw the lever rests on. Can That be adjusted to drop the idle? I ask because the PO said he scoped the TPS and sdjusted it cuz it was off a bit. I know you can't adjust the TPS but maybe he tweaked that screw and the new one is confused? I'm grasping at straws here folks!
Does the IAC have effect on more than just idle like at speed?
Why would a new TPS cause a sticky high idle when there wasn't one before or is there another part that's not working? WHy does pulling on the lever idle it down anyways?
I need some insight on how to trouble shoot this. If someone can answer all or ANY of the questions I'd be eternally indebted!
96, 4 liter, 150km , AW4, NP231
The rig has been studdering on the highway randomly and at idle. On the highway it almost seems like it's missing but the rpms don't drop. The RPM bounces quite a bit at idle in gear from 800 to 1500 sometimes. I got 2 code 43s on the obd2 when it bucked really bad at a hot start, took it to the shop , they scanned it and came upwith a misfire in #3, nothing else.
I replaced plugs (old #3 plug lookes liek the others fyi) and wires and it idles better and has a bit more power, but the studdering is still there randomly, sometimes on a cold start then fine at speed, sometimes on a hot start only then fine at speed, sometimes hot or cold and at speed .
When I come to a stop, often it idles bouncing between 1100 and 750. THis is not a constant thing though. Sometimes it's fine. Today was the worst. It started fine warmed up fine and drove fine for about 10 minutes then the bucking at speed and crappy unstable idle happened coasting to a stop and idling in D. RPMs wer going all over between 8 and 1200. I shifted at the stop to N and In Neutral it seemed fine though........???? Tranny shifts great and is strong fyi.
On a side note It also doesn't always want to drop when I let my foot off at highway speeds till I tap the brake. This symptom sounded like TPS to me
so I just replaced the TPS with a BWD/Borg Warner (please lmk if I got the wrong brand!) a few minutes ago and now when I rev it and let off it "sticks" around 1100 unless I pull up a bit on the throttle lever on the body. Once I tapped the IACV a couple times and it dropped to normal. Could the IAC be crapping out as well? I find it strange that when I changed the TPS this new sticky high idle thing arose. Faulty TPS ? When it went on I did have to put it on at a slight angle to get it to align but I assume that's just preloading right, or is it faulty? I need to know so I can return it before it's too late. There's a small screw the lever rests on. Can That be adjusted to drop the idle? I ask because the PO said he scoped the TPS and sdjusted it cuz it was off a bit. I know you can't adjust the TPS but maybe he tweaked that screw and the new one is confused? I'm grasping at straws here folks!
Does the IAC have effect on more than just idle like at speed?
Why would a new TPS cause a sticky high idle when there wasn't one before or is there another part that's not working? WHy does pulling on the lever idle it down anyways?
I need some insight on how to trouble shoot this. If someone can answer all or ANY of the questions I'd be eternally indebted!
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