Rough idle, after new exhaust and airfilter
#1
Rough idle, after new exhaust and airfilter
Hi
2 weeks ago i swap out the old rusty exhaust with a new from fabspeed, also i put on open power filters from fabspeed.
i fell like the car has lost power, and it has a rough idle. and i have a CEL for P1128 and P1130. (O2 sensors are brand new.)
When i take the car to the highway and give it some hard pulls, the idle will get just fine, and the engine runs smooth. If i let the car cool off, the problem will turn back.
Even if i drive slowly thorug trafik and the engine gets up to temperature, the idle wont get better, unless i give some hard pulls on the highway.
any experiences to share ?
2 weeks ago i swap out the old rusty exhaust with a new from fabspeed, also i put on open power filters from fabspeed.
i fell like the car has lost power, and it has a rough idle. and i have a CEL for P1128 and P1130. (O2 sensors are brand new.)
When i take the car to the highway and give it some hard pulls, the idle will get just fine, and the engine runs smooth. If i let the car cool off, the problem will turn back.
Even if i drive slowly thorug trafik and the engine gets up to temperature, the idle wont get better, unless i give some hard pulls on the highway.
any experiences to share ?
#2
Hi
2 weeks ago i swap out the old rusty exhaust with a new from fabspeed, also i put on open power filters from fabspeed.
i fell like the car has lost power, and it has a rough idle. and i have a CEL for P1128 and P1130. (O2 sensors are brand new.)
When i take the car to the highway and give it some hard pulls, the idle will get just fine, and the engine runs smooth. If i let the car cool off, the problem will turn back.
Even if i drive slowly thorug trafik and the engine gets up to temperature, the idle wont get better, unless i give some hard pulls on the highway.
any experiences to share ?
2 weeks ago i swap out the old rusty exhaust with a new from fabspeed, also i put on open power filters from fabspeed.
i fell like the car has lost power, and it has a rough idle. and i have a CEL for P1128 and P1130. (O2 sensors are brand new.)
When i take the car to the highway and give it some hard pulls, the idle will get just fine, and the engine runs smooth. If i let the car cool off, the problem will turn back.
Even if i drive slowly thorug trafik and the engine gets up to temperature, the idle wont get better, unless i give some hard pulls on the highway.
any experiences to share ?
#3
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Your double posts are confusing. In your other post you said " 2 weeks ago i got new fabspeed cats and muflers, new 02 sensors and new carbon airfilter intake. All installed."
Now in this one you say " 2 weeks ago i swap out the old rusty exhaust with a new from fabspeed, also i put on open power filters from fabspeed"
Which is it? Or do those things mean the same thing? I would suggest putting the stock air box back on as it is well known aftermarket filters cause these types of problems, especially related to the MAF sensor. Clean the MAF sensor with MAF cleaner. After that, clear the codes and reset the DME by disconnecting the negative battery lead. With new O2 sensors you need to remap the DME so new values can be set based on feedback from the new O2 sensors. You have to approach the problem step by step. You need to backtrack what you have done...is it the new air intake, MAF sensor, new O2 sensors, what type of O2 sensors, did you get them plugged in the right order?
Now in this one you say " 2 weeks ago i swap out the old rusty exhaust with a new from fabspeed, also i put on open power filters from fabspeed"
Which is it? Or do those things mean the same thing? I would suggest putting the stock air box back on as it is well known aftermarket filters cause these types of problems, especially related to the MAF sensor. Clean the MAF sensor with MAF cleaner. After that, clear the codes and reset the DME by disconnecting the negative battery lead. With new O2 sensors you need to remap the DME so new values can be set based on feedback from the new O2 sensors. You have to approach the problem step by step. You need to backtrack what you have done...is it the new air intake, MAF sensor, new O2 sensors, what type of O2 sensors, did you get them plugged in the right order?
#4
i have testet the oilfiller tuper afterward, and when a take of the cap, the idle gets even worse, so i guess the oil filler tube is ok. But i have not checked the vacum line
#5
Okay new Update
i put the oem air filter back on, but no real difference to feel.
idle is still rough and around 750 rpm to 850.
i did notice that the air pump didn't run, can that trick the o2 sensors ?
se o2 readings in picture
#6
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Did you clean the MAF sensor? Did you clear all the codes? Did you reset the DME? The DME needs feedback from the MAF sensor and O2 sensors to run right. So you need to get it set back to base values and then let it adapt. Is the idle hunting when it is running poorly at idle? The SAI pump not running will throw a separate code. But it does have it's purpose, pumping air into the exhaust system at startup to light up the cats faster while keeping the air/fuel mixture at a richer state, so that will affect the O2 sensor readings at startup. It's a balanced and complicated loop at startup until the engine reaches normal operating temperature.
#7
No I didn't clean the maf sensors. Wil try that tomorrow.
all codes cleared with bosh testing computer via OBD2 port
how do I reset the DME? Do I need to pull the power from battery, or is there an easy way?
all codes cleared with bosh testing computer via OBD2 port
how do I reset the DME? Do I need to pull the power from battery, or is there an easy way?
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#10
Race Car
TB - Throttle Body
Was working on a fellow forum members 99' and he didnt have the throttle cable correctly in place, caused a whole lot of issues so thought i'd ask just in case.
RE battery 5 minutes would be heaps - others can confirm/might have a more specific time
Was working on a fellow forum members 99' and he didnt have the throttle cable correctly in place, caused a whole lot of issues so thought i'd ask just in case.
RE battery 5 minutes would be heaps - others can confirm/might have a more specific time
#11
I will clean throttle body and MAF sensor today, - update on that will follow
My MAF i showing 6,25-6,50 on the bosch tester when idle. i gues this number should be lower, and constantly, not jumping up and down.
My MAF i showing 6,25-6,50 on the bosch tester when idle. i gues this number should be lower, and constantly, not jumping up and down.
#12
Update!
Cleaned out throttlebody and MAF sensor with MAF clean, took the power from the batteri for 5-10 min, drove it for 20 mins round town (slow trafik)
But no difference, stil same rough "rolling" idle.
any moore ideas?
btw. O2 sensors are new but not OEM, could these aftermarket sensors be the reason?
Cleaned out throttlebody and MAF sensor with MAF clean, took the power from the batteri for 5-10 min, drove it for 20 mins round town (slow trafik)
But no difference, stil same rough "rolling" idle.
any moore ideas?
btw. O2 sensors are new but not OEM, could these aftermarket sensors be the reason?
#13
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A hunting idle is often caused by the Idle Control Valve (ICV) which is on the TB. You have to remove it and clean it out. Yes, our cars are very particular when it comes to the O2 sensors. What aftermarket ones did you put in?