surging in drive (4th gear)

[hold-on]

My car has been surging for sometime...originally it brought up a fault code 35 so I cleaned throttle body and iac valve....and it went away......now the surging is back but the iac and throttle body is clean.

Can anyone help please.....oh ocassionally there is a miss or two...complete loss of power for a split 2nd....I susspect 2 problems

Cheers
for any help

 

[hako]

If it surged in 4th above 80kph when the torque converter is locked solid it could be the TCC playing up and locking/unlocking the TQ. But if not then its the usual culprits to check - though you probably have checked these already. The coil pack may have a split in one of the coils, the CAS could be starting to fail, fuel filter may be blocked, fuel pump may be failing (have you run low on fuel lately?) and plugs and leads could also be checked. Good Luck.

 

[jazza21]

Cat Converter?

Check out the Catalytic Converter, I think I had a very similar issue. Mine was all broken up and caused back pressure in the exhaust. Replaced it and it worked a treat.

 

[hold-on]

forgot to mention, the car only has surges in 4th @ about 1700 - 1900 rpm
@ 90 - 98km it has the occassional loss of power / miss for a split 2nd. It also usually only does this after at least half hour of open road driving.......
Could the air filter be just dirty?????

 

[hako]

Put it in 3rd and see if it does the same as it still sound like the transmission lockup clutch to me.

 

[hold-on]

only in 4th mate all other gears a fine!!!!!!! even 4th is fine once above 2000rpm.......would a trans service fix?????? if you still think that is the prob.
im stll not sure I thinnk it may iac valve tired or airflow meter??????
I hope you have a fair idea of prob Hako coz I am stumped!!!!

 

[hako]

I'd first find a reputable auto trans place and explain your problem ask if it could be the TCC (torque converter clutch). They should give you an honest explanation if they are a good shop. There is probably a way of eliminating the lockup to check yourself for sure....maybe do a google search on 4l60e.

 

[hako]

This link give all common 4l60e faults and possible refers to yours as 'shuddering' ....anyway have a read of it and see if anything there matches your problem.
The other thing to consider is that if the trans has not had a service for years then it would not hurt to get it done...also a full flush.
http://impalassforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=4;t=006666;p=

 

[hold-on]

Cheers hako I will have a look... I did have trans serviced 20,000km ago...
I will prob make a start and go through the basics......how to I check coil pack??????? and leads?????? I will replace plugs I actually did leads 6mths ago so I would not suspect them.......I will clean my k & n panel filter....forgot to mention I have a cai kit so a slightly dirty air filter could cause this?????