160º T-Stat + Stock Chip = No Open Loop?
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
160º T-Stat + Stock Chip = No Open Loop?
95% of the time, my car runs between 160º-170º this time of the year...so my question is, am I ever getting out of Closed Loop? I've heard that with a 160º stat, you have to reprogram your ECM to function with the lower stat...but I mean...I dunno, what's the scoop? Thanks!
Car is an 87, few bolt ons.
Dynoed at 225rwhp/355rwtq
Runs 13.6@100mph in the quarter.
Car is an 87, few bolt ons.
Dynoed at 225rwhp/355rwtq
Runs 13.6@100mph in the quarter.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
You should be fine. Hell my car wouldn't get above 135 a few times times in the dead cold of winter when it was near 0* out. As long as your exhaust heats your O2 sensor enough it'll go closed loop.
Drifting
Joined: Mar 2001
Posts: 1,636
Likes: 3
From: Lafayette IN
Re: (TIMSPEED)
I think the question you are really asking is "Is my car ever going to go into closed loop".
Your car starts off in open loop and you have variables in the ECM that will then allow the car to enter closed loop, which will enable using data from the O2.
Your car starts off in open loop and you have variables in the ECM that will then allow the car to enter closed loop, which will enable using data from the O2.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: (HighHopes85)
I take it you do not have a scan tool to see if the car is in closed loop? If not you can do this:
The ALDL is located under the dash to the right of the steering wheel. Use the ends of a paper clip to jumper pins A & B (upper right) and start the engine. This will put the ECM into "diagnostic mode".
The SES will flash at a fast rate till the engine is warmed up and in closed loop mode. Then the On/Off flash duration will indicate Righ/Lean condition; so should be of equal duration. Bring the engine from idle up to several RPM levels and monitor the flashes. If flashes level out to equal duration in each case, all is well.
If the SES flashes never slow down to about 1Hz, the ECM is not going into closed loop mode. In that case suspect the O2 sensor or the coolant temp sw. Here a scan tool would be very helpful.
The ALDL is located under the dash to the right of the steering wheel. Use the ends of a paper clip to jumper pins A & B (upper right) and start the engine. This will put the ECM into "diagnostic mode".
The SES will flash at a fast rate till the engine is warmed up and in closed loop mode. Then the On/Off flash duration will indicate Righ/Lean condition; so should be of equal duration. Bring the engine from idle up to several RPM levels and monitor the flashes. If flashes level out to equal duration in each case, all is well.
If the SES flashes never slow down to about 1Hz, the ECM is not going into closed loop mode. In that case suspect the O2 sensor or the coolant temp sw. Here a scan tool would be very helpful.
