Hey guys,

my car is nearly running right again, ive replaced the ignition module, TPS and set the timing as it was a little off.

The only thing now is that it idles a bit lower than it used to in Park, even after its gone into closed loop, then when you put it in drive or reverse the revs drop right down to about 400 and it sounds like the cars struggling a little bit, it never cuts out though.

then when setting off slowly it feels a bit rumbly like its misfiring ? however if you step on the gas a bit it takes off no problem and goes like a train !! is this just an idle issue and the IAC needs cleaned or something ?

 

Sounds like your tps may need adjusting. You can always reset the IAC. Thats a really low idle. Any lower it would quit. My car could never survive idling lower than 600 but our cars are different.

 

the GTA idles around 500 in drive when at normal temps

 

i set the TPS to .54 last week, i checked it and it had moved to .74 so i musnt of had the screws tight enough.

so it sounds like the IAC needs adjusted then to get the rpms higher when its in drive ?

 

or your tach is a bit off.

 

well if it was just the actual tach reading then the car would be running ok, i can hear the idle going up and down slightly

 

Turn key to on position for a couple seconds, then disconnect the IAC. Turn key off then come around to plug in your connector back to your IAC. Then your done. See what happens

 

ok i'll give it a go, just read the tech article on here too and it says i have to put the car in diagnostic mode first by putting the paper clip in the ALDL connector then start the engine, i thought if you had the paperclip in the connector and started the engine it wrecks the ECU ?

 

no no. you put the paper clip in, turn the ignition on wait 1 minute. then unplug the IAC, turn ignition off and pull out paper clip. then start car and make your minimum idle adjustment, when you have it where you want it shut it off, plug the IAC in and re start the car

 

My mistake i didnt see what yr your car was. he is right you have to get the car in diagnostic mode before resetting the IAC. Im so use to Speed Density ECM that the computer does the work, Yours has a screw on the back of the TB you can change idle. But the process is still the same way though. Just make sure you turn the key off first before taking out the paper clip, i learned years ago not to do that.

 

thanks guys, i think ive got other problems though. I had to drive the car upto the paintshop today which is about 6 miles from me, this is the first time the car has been for a proper drive since December.

Im fairly certain its misfiring, it does it at high speeds too as i noticed once i got onto the motorway, once upto speed it runs fine but the slightest touch of the accelerator and it bogs down, you have to really step on the gas for it to clear and pick up the power again.

 

you check the resistance on the coil? Make sure rotor button has no burn marks, if nothing id check into the pick up coil in the distributor next.

 

thanks mate, i'll check into that, ive gotta pick it up from the paintshop tomorrow so as long as it gets me home where its safe and sound in the garage i will be happy and i can start looking at stuff

 

hey guys, well i drove the car home from the paintshop and it was driving a lot better, it wasnt idiling as low when stopped at lights etc and it seemed to take off a bit better, however its still a bit grumbly when you put your foot on the accelerator at whatever speed your going and its struggling, if you really put your foot down it takes off though,

Its like it doesnt quite know what rpms its at or something because if your just cruising along the rpms will drop down like its changed into overdrive (well not quite) and thats what makes it bog down, so you have to keep giving it a bit of gas

 

Give it your preferred brand of fuel system cleaner. I've used seafoam, but I'm gonna try Justice Brothers next time.

 

fuel cleaner ? never even thought it would be something like that, one of the better brands over here in the uk is Redex, for fuel injection systems, i usually put a bottle of that in the tank once a year, just havnt done it this year

 

You mentioned it had sat for a while. My car was stored over winter, and when I bought it, it had sort of a stumble/hesitation. A can of seafoam in the gas cleared it right up, and cleaning and resetting the IAC made it run like a champ!

 

sounds like fuel injectors, couldn't hurt to change the fuel filter out too

 

fuel filter was new last year, i checked the injectors last year when i was having other problems and they checked out ok, i'll stick a bottle of Redex in and clean the IAC out and see what happens.

I also noticed yesterday when it was idiling it was popping slightly from the exhaust now and then, like when you have the wires on the wrong plugs, but they arent as i checked

wont make much diffference unless i can fix my drivers door though, im starting to hate this car at the minute

 

drivers door fixed ! so at the weekend im hopefully gonna take it for a spin after cleaning the IAC, i'll check the cap and rotor too and then go get some injector cleaner.

Whats the best stuff to clean the IAC with ? i dont want to damage it, i usually just spray things like that with WD40 as its used for just about everything, especially if its electrical too