Runs like crap after 170F
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From: Springhill, FL
Runs like crap after 170F I'm stumped. The car runs perfect when its cold, idle and cruising. But as soon as it warms up past 170F coolant temp it wont idle(surging and failing). And on the road it bucks and sputters like its on 1 cylinder at anything below WOT.
For backround I just removed my procharger. And I'm starting with a stock tune for a 98. It still has all the other mods in my sig. What baffles me though is that when I put the cam in two years ago it was fine with the stock tune. I drove the damn thing around and even took it to the track with the cam in it and no tune for over 9 months.
I'm tuning with EFIlive, I'm not looking for optimal performance here..just want the thing to be drivable. Any ideas ?
For backround I just removed my procharger. And I'm starting with a stock tune for a 98. It still has all the other mods in my sig. What baffles me though is that when I put the cam in two years ago it was fine with the stock tune. I drove the damn thing around and even took it to the track with the cam in it and no tune for over 9 months.
I'm tuning with EFIlive, I'm not looking for optimal performance here..just want the thing to be drivable. Any ideas ?
Last edited by MawneeC5; Jul 9, 2007 at 05:53 AM.
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From: Katherine N.T Australia
Originally Posted by MawneeC5
I'm stumped. The car runs perfect when its cold, idle and cruising. But as soon as it crosses 170F coolant temp it wont idle(surging and failing). And on the road it bucks and sputters like its on 1 cylinder at anything below WOT.
For backround I just removed my procharger. And I'm starting with a stock tune for a 98. It still has all the other mods in my sig. What baffles me though is that when I put the cam in two years ago it was fine with the stock tune. I drove the damn thing around and even took it to the track with the cam in it and no tune for over 9 months.
I'm tuning with EFIlive, I'm not looking for optimal performance here..just want the thing to be drivable. Any ideas ?
For backround I just removed my procharger. And I'm starting with a stock tune for a 98. It still has all the other mods in my sig. What baffles me though is that when I put the cam in two years ago it was fine with the stock tune. I drove the damn thing around and even took it to the track with the cam in it and no tune for over 9 months.
I'm tuning with EFIlive, I'm not looking for optimal performance here..just want the thing to be drivable. Any ideas ?
There are quite a lot of ECT/fueling tables that should be adjusted when you start running your motor cooler. Have a look around in your tune.
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From: Springhill, FL
Originally Posted by macca_779
There are quite a lot of ECT/fueling tables that should be adjusted when you start running your motor cooler. Have a look around in your tune.
The idle airflow table is based around ECT so there's a good place to start with the idle. As far as the sputtering you may need to adjust the throttle follower. That'll help smooth things out when moving from a stop.
That's not a huge cam you're running so it shouldn't need a whole lot of change from stock.
Are you using a completely stock 98 tune or just some tables copied from a stock 98 tune?
That's not a huge cam you're running so it shouldn't need a whole lot of change from stock.
Are you using a completely stock 98 tune or just some tables copied from a stock 98 tune?
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From: Springhill, FL
Originally Posted by My90Iroc
The idle airflow table is based around ECT so there's a good place to start with the idle. As far as the sputtering you may need to adjust the throttle follower. That'll help smooth things out when moving from a stop.
That's not a huge cam you're running so it shouldn't need a whole lot of change from stock.
Are you using a completely stock 98 tune or just some tables copied from a stock 98 tune?
That's not a huge cam you're running so it shouldn't need a whole lot of change from stock.
Are you using a completely stock 98 tune or just some tables copied from a stock 98 tune?
I've since tried to work around the problem by removing my thermostat and setting my fans to keep the coolant at 150. Problem still shows up
its not directly linked to the coolant temp. Thread Starter
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From: Springhill, FL
Originally Posted by 1320FEVER
Do you think maybe its when your engine is going into "closed loop" mode, this might be happening? At what temperature is you "closed loop enable" set at?
Once it kicks into closed loop my O2s(all 4) are bouncing all over the place and my LTFTs are bouncing from -1% to -18%.
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Originally Posted by MawneeC5
Thats exactly what it was. I forced it into open loop tonight and it ran perfect. So now to figure out why closed loop isnt functioning right.
Once it kicks into closed loop my O2s(all 4) are bouncing all over the place and my LTFTs are bouncing from -1% to -18%.
Once it kicks into closed loop my O2s(all 4) are bouncing all over the place and my LTFTs are bouncing from -1% to -18%.
I've been running open loop for the last year and a half with no problems at all. The maf can adjust for weather and altitude so if your ve tune is right you shouldn't see any ill effects from running open loop all the time.
Also don't forget to reset your LTFTs otherwise the car will be using the stored values in there and you'll be tuning around that.
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