Hi

No fault codes as of yet but pretty much every cold morning it has lumpy idle when it starts. but only seems to last about a min or two. then like when the sai cuts out it settles down. or is there an automatic choke on these?

if it was failing MAF would it not be an issue all the time and not just cold start

was also getting mis fires on cylinder 4 so tried a pack from a mate. mis fires down to none or a couple but way better. was going to change plugs but im just guessing really

any suggestions??

 

The sai system pumps more air into the exhaust to warm the cat up quicker when the car is cold, if your manifold air temp sensor is sooted up, this can make the running worse as the ecu searches for accurate sensor readings to adjust the fueling.

 

A clean of the MAF and air temp sensor, and a clean of the throttle body can make life a lot easier this time of year.

 

You could also just remove the system, but you may get the MIL light coming on even if you fit resistors.

The sai system pumps more air into the exhaust to warm the cat up quicker when the car is cold, if your manifold air temp sensor is sooted up, this can make the running worse as the ecu searches for accurate sensor readings to adjust the fueling.

 

A clean of the MAF and air temp sensor, and a clean of the throttle body can make life a lot easier this time of year.

 

You could also just remove the system, but you may get the MIL light coming on even if you fit resistors.

 

have some isopropyl alcohol from before so will give them a clean. im guessing the air temp sensor is the one on top the manifold at the throttle body. iirc i should dis connect the battery as not to mess up alignment on throttle body

certainly only started happening when really cold weather kicked in and after an overnight freeze

have the resistors lying around somewhere too so if doesnt work can always try the delete

Clean the maf by removing the sensor from the intake tube, then fill a small resealable polythene sandwich bag with about 1 1/2" of IPA, drop the sensor in and seal it then give it a gentle shake and leave it for a few minutes. Remove it from the bag and leave to air dry for 5 minutes.

 

You can do the air temp sensor the same way, and you are correct about it's location.

 

I used to clean the throttle body by removing the body from the manifold, but not disconnecting the wiring, I would then get swmbo to hold the pedal to the floor while I cleaned it. I now have VCDS, so I don't bother anymore, I just disconnect it, clean it, refit it and carry out a throttle body alignment with VCDS at the end.

 

Hope it helps.

Edited 11 November, 20169 yr by kentphil1

Clean the maf by removing the sensor from the intake tube, then fill a small resealable polythene sandwich bag with about 1 1/2" of IPA, drop the sensor in and seal it then give it a gentle shake and leave it for a few minutes. Remove it from the bag and leave to air dry for 5 minutes.

 

You can do the air temp sensor the same way, and you are correct about it's location.

 

I used to clean the throttle body by removing the body from the manifold, but not disconnecting the wiring, I would then get swmbo to hold the pedal to the floor while I cleaned it. I now have VCDS, so I don't bother anymore, I just disconnect it, clean it, refit it and carry out a throttle body alignment with VCDS at the end.

 

Hope it helps.

Did help mate. Made a massive difference and not surprised as temp sensor and TB were fairly gunked up

Hasnt stuttered once since and no more problem on cold mornings

Well worth it and and easy task

thanks for advice

You're very welcome mate :thumbup: