It Runs! But runs very poorly when hot??
07-30-2003, 10:03 AM
#21
Teching In
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Re: It Runs! But runs very poorly when hot?? Sensor 2 sounds bad. Sensor 1 seems to react fine. Also make sure to pin out the harness to make sure nothing is pinned or wired backwards.
As soon as you described your idle as rolling and hunting that immediatly pointed me to a air fuel ratio hunting issue in closed loop control mode. Air leaks after the air meter will cause most of the same issues. Sounds like your on the right track. Good luck.
As soon as you described your idle as rolling and hunting that immediatly pointed me to a air fuel ratio hunting issue in closed loop control mode. Air leaks after the air meter will cause most of the same issues. Sounds like your on the right track. Good luck.
07-30-2003, 11:07 AM
#22
07-30-2003, 12:09 PM
#23
Re: It Runs! But runs very poorly when hot?? S1's are the fronts. 
Just so everyone is on the same page:
B1S1= drivers side front
B1S2= drivers side rear
B2S1= passenger side front
B2S2= passenger side rear
When you eliminate the cats, you get rid of B1S2 & B2S2.
Just so everyone is on the same page:
B1S1= drivers side front
B1S2= drivers side rear
B2S1= passenger side front
B2S2= passenger side rear
When you eliminate the cats, you get rid of B1S2 & B2S2.
__________________
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
07-31-2003, 08:38 AM
#24
Launching!
Thread Starter
Re: It Runs! But runs very poorly when hot?? Okay. So yesterday I logged B1S1 and B2S1 and they both looked very similar. Up and down alot, but then after awhile, they settled: S1 at around 850, S2 at around 925 or so. This is very frustrating because the whole time I was logging, the car actually idled fairly nicely. It varied from about 650 to 750rpm but it wasn't hunting. The timing moves quite a bit too. It stays near 22, but moves around from 18 to 26 or so. Jabbing the throttle would get things going (both O2s go crazy, trims go up, etc.), but it all settled out again when back to idle. I even knocked it into the limiter a few times.
I drove the car this AM and the idle is better than it has been typically, but it still hunts around. It wasn't as steady as yesterday evening. Maybe I should just always have ATAP and a laptop connected.
Also, it still smokes at idle and smells way rich.
I wish I knew of a shop around here (not that I have any money left). Bugs me that it's running rich, but I can live with it in its current state of drivability (don't have to manually keep it from dying at stop lights which is embarrassing). Obviously I don't think this is going to last though.
So, since the problem is intermittent, maybe one or 2 of the injectors are just *****. Maybe it's elves.
I drove the car this AM and the idle is better than it has been typically, but it still hunts around. It wasn't as steady as yesterday evening. Maybe I should just always have ATAP and a laptop connected.
Also, it still smokes at idle and smells way rich.
I wish I knew of a shop around here (not that I have any money left). Bugs me that it's running rich, but I can live with it in its current state of drivability (don't have to manually keep it from dying at stop lights which is embarrassing). Obviously I don't think this is going to last though.
So, since the problem is intermittent, maybe one or 2 of the injectors are just *****. Maybe it's elves.
07-31-2003, 10:44 AM
#25
LS1Tech Co-Founder
iTrader: (34)
Re: It Runs! But runs very poorly when hot?? ?
If you have a front o2 that is sitting at 450mv it's a big problem. Car will run rich, and it will surge and maybe stall out. It might be also fouling out your plugs.
If you have a front o2 that is sitting at 450mv it's a big problem. Car will run rich, and it will surge and maybe stall out. It might be also fouling out your plugs.
07-31-2003, 11:30 AM
#26
Launching!
Thread Starter
Re: It Runs! But runs very poorly when hot?? No no. In my first post about logging O2s I had it wrong. I had thought (as had some others) that B1 meant front, but John@Speartech pointed out that S1 means front. So that last post was about how I logged both S1 O2s and they track pretty closely (although the S2 reads slightly higher).
So, unfortunately, I really don't have a bad O2 - unless that 40-50mV difference is enough to hose things.
So, unfortunately, I really don't have a bad O2 - unless that 40-50mV difference is enough to hose things.
08-04-2003, 08:50 AM
#27
Launching!
Thread Starter
Re: It Runs! But runs very poorly when hot?? Just to add to the mystery, if I drive the car for at least an hour straight, then everything clears up and it's fine. Good idle, everything. But if it sits for more than 20 minutes, it's back to stinky town.
Also, it's not just idle. I'm on the freeway in the morning before the temp gets to 160. So, I'm cruising in 6th by the time it goes to 180 and switches to closed loop. I can feel it switch over. The car lurches and stumbles everytime it hits 180*. It tends to recover somewhat and I can continue to cruise along. But of course it wants to die at the first stop.
Anyone know of a good shop in the Raleigh/Durham area? This is way past annoying.
Also, it's not just idle. I'm on the freeway in the morning before the temp gets to 160. So, I'm cruising in 6th by the time it goes to 180 and switches to closed loop. I can feel it switch over. The car lurches and stumbles everytime it hits 180*. It tends to recover somewhat and I can continue to cruise along. But of course it wants to die at the first stop.
Anyone know of a good shop in the Raleigh/Durham area? This is way past annoying.
