Car Runs fine when the engine is cold/cool but lags when hot.
#1
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Hey, My S2 runs perfectly when the engine is cool, or warm. as soon as it gets hot, as in has a bit of a work out or I sit at a set of lights and the engine temps rise up to hot (still within normal perameters) the car becomes very lagy. It takes a while to get it cool enough to gain the power back but even still all i need to do (even on a cold night) is sit at a set of lights for 2 mins and it becomes lagy again.
Any ideas?
Replaced list:
Fuel filter
Air filter
Leads
Plugs
O2 Sensor
Coolent temp sens
AFM
Any ideas?
Replaced list:
Fuel filter
Air filter
Leads
Plugs
O2 Sensor
Coolent temp sens
AFM
#4
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hello
I had a same problem,take the car to mechanic did all that, what you had done so fare.And it vas some graunding on the bac of the engine to the main bord.And since that evereting is OK.
I hop this will help you.
I had a same problem,take the car to mechanic did all that, what you had done so fare.And it vas some graunding on the bac of the engine to the main bord.And since that evereting is OK.
I hop this will help you.
#5
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jozsef, i think i get what you're saying but could you maybe reword it i dont quite get it, but i think you're onto something... My alt is playing up and volts are dropping bellow 12 and spiking above 15. Not to mention my entire fuel system is fouled by ethanol mixing up dirt into the system... I may almost be at a perfect 944 (for a few more weeks)
#6
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hello
sorry for the waith.
what i mant to say my car had the same problem.wee replaced many of the parts you mantioned.But no vail.finely they checked the graunds and the one on the back of the engine is vas dirty,whit some cleaning, the car is runs ok.
sorry for the waith.
what i mant to say my car had the same problem.wee replaced many of the parts you mantioned.But no vail.finely they checked the graunds and the one on the back of the engine is vas dirty,whit some cleaning, the car is runs ok.
#7
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I'm gonna re enter this question...
Ok, basically the car runs hot... on a warm night like tonight, my thermo fans pretty much dont switch off... they do but they're back on within a couple mins. On the drive up to sydney, the temps were in the hot range the whole way up (hot, just before the thermo fan switch) and that was cruising in 5th at 110..The engine runs like this pretty much from the get go. When the engine is like this its VERY lagy and it also seems to hesitate through the revs missing and pulling all the way through. It gets worse in heavy traffic... ei chaps/ city driving.
On a normal day/night (22deg) the car will take 15-20 mins to get to this stage. Prior to this it runs perfectly normal.
Another thing acossiated with this problem is a lack of constant voltage with the volt meter vairying as the lights go on and off on the indicator. So much so that the headlights and interior light dim. Once the engine is revving again, this goes away.
I also get very large drops in RPM (down to fuel cutt) when clutching when i stop at lights, or gently touching the throttle at lights, followed by the engine picking up then hunting then settling down.
These three problems happen at the same time, whether its related I dont know... I belive the cutting and hunting revs is due to a clogged idle control valve.
Things its not:
Intake temp sensor
Airflow meter (barn door style)
Engine coolent temp sensor
colapsed cat
alternator
any ideas on what it could be? any stories...
thanks
nick
Ok, basically the car runs hot... on a warm night like tonight, my thermo fans pretty much dont switch off... they do but they're back on within a couple mins. On the drive up to sydney, the temps were in the hot range the whole way up (hot, just before the thermo fan switch) and that was cruising in 5th at 110..The engine runs like this pretty much from the get go. When the engine is like this its VERY lagy and it also seems to hesitate through the revs missing and pulling all the way through. It gets worse in heavy traffic... ei chaps/ city driving.
On a normal day/night (22deg) the car will take 15-20 mins to get to this stage. Prior to this it runs perfectly normal.
Another thing acossiated with this problem is a lack of constant voltage with the volt meter vairying as the lights go on and off on the indicator. So much so that the headlights and interior light dim. Once the engine is revving again, this goes away.
I also get very large drops in RPM (down to fuel cutt) when clutching when i stop at lights, or gently touching the throttle at lights, followed by the engine picking up then hunting then settling down.
These three problems happen at the same time, whether its related I dont know... I belive the cutting and hunting revs is due to a clogged idle control valve.
Things its not:
Intake temp sensor
Airflow meter (barn door style)
Engine coolent temp sensor
colapsed cat
alternator
any ideas on what it could be? any stories...
thanks
nick
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#8
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I think Jozself is on the right track. Grounding is a big problem with these cars. Some guy makes these real pretty cable setups that are real expensive. But you can do the same thing by drilling out the stud that the ground cable mounts to and install a longer ground cable and mount it to the engine. It's a cheep upgrade! Good Luck' Bob
#9
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I've recently had my thermostat replaced and it seems to have made a difference but I'm still getting major trouble with voltage after driving the car in stop start conditions with the revs dropping down to 10v. I dont have any trouble with the car normally and usually copes well with load as I've been testing it once every now and then with load nd it always copes. Tonight it seems the alt failed intimitantly as the car **** itself and automatically reved out to 4000 when I loaded up the elec system and then switched on the aircon.
I get why there may be a problem, but not something that is as random as this.
I still have a laggy problem which seems to get worse in the stop start conditions but I'm thinking its along the lines of high intake temps.
Another thing which happens in stop start conditions or driving at around 35 at a low RPM is that the revs drop down very low when i clutch in which again leads to alt failure...
If anyone knows or has an idea as to what this could be I would really appriciate any help as I'm about to lose my license and wont be able to sort this stuff out any longer
Thanks in advance
nciik
I get why there may be a problem, but not something that is as random as this.
I still have a laggy problem which seems to get worse in the stop start conditions but I'm thinking its along the lines of high intake temps.
Another thing which happens in stop start conditions or driving at around 35 at a low RPM is that the revs drop down very low when i clutch in which again leads to alt failure...
If anyone knows or has an idea as to what this could be I would really appriciate any help as I'm about to lose my license and wont be able to sort this stuff out any longer
Thanks in advance
nciik