vs 5.0l surging and missfiring problems

[12345678910]

Hey all, im posting this because i am having some problems with my calais 5.0l. Basically it will idle at around 1500rpm any time not just when its cold and sometimes even up to 2000rpm it will drop as you put it in drive. The throttle body and iac valve have been throughly cleaned so im assuming their not the problem? The second problem that im having is a slight miss when the engine is in labour ie up hills etc, it varys from day to day though, sometimes it will obtain a chronic miss throughout the rev range and even on idle, It also surges from time to time if you acclerate hard around corners, im leaning towards maybe dirty injectors as the cars part time gas powered. As for the ignition componets i have replaced the rotor button dizzy cap leads and plugs also the ignition module as it had failed a few months earlier. I havnt yet brought up any fault codes so that needs to be done still. Another thing is that the fuel pump was replaced recently with a cheap after market version as that had failed to, maybe that has something to do with the surging? Any help would be greatly appreciated, cheers Rob.

 

[vscalaishsv]

try a new bosh coil maybe that's **** it self

 

[VrWagz1]

Loose clamp on the fuel line somwhere maybe

 

[12345678910]

yeah just checked for loose fuel hoses and vacuum lines and couldnt find any issues also replaced the coil and still no go. Ive also ruled out the injectors as the miss dosent stop when its running on gas cheers for the advice.

 

[BlackVXGTS]

Re your first problem, was the throttle body removed when it was cleaned? Check for play in the throttle cable, it needs to be quite loose. If it's tight it may be the cause of your high idle.

 

[12345678910]

yeah i had a look at the throttle cable and its was fairly loose. I think its just a faulty iac valve because i pulled the throttle body off and gave it a good clean out again and its still idling at 1500rpm.

 

[12345678910]

its now started to miss badly on idle and throughout the rev range hot or cold i cant work it out.

 

[slepar]

i am also having this exact problem except for the missfiring, my car surges and sometimes idles at around 1500, ive changed leads plugs rotor cap and button and gas mixer and yea cant seem to figure out what it is, i dont know if the problem is still there when its on petrol because the fuel pump is stuffed and it doesnt run on petrol, but it is extremely annoying so if u fix it please tell me so i can try the same

cheers

 

[steve44]

a mates having same problem in his 92 caprice 5.0l
does anyone know???

 

[NeilB]

Try replacing the Temp Sensor that goes to the ECU, its the 1 with the blue connector, get the Oxy sensor checked and look for fault codes.