idle problem on mx5 supercharged ?
Discussion
Hello everybody !
I have a little problem with my supercharged mx5 (t28 turbo kit)
last week I have an alarm problem and I disconnect the battery during one night
when I reconnect her the car don't run normally
the idle is unstable when the engine is hot
when it's cold the car is a 850 trs/min but move like an old V8 or like it's on 3 cylinder
and when it's hot the car stop immediatly if I don't leave my foot on the accelerator pedal
on boost all run good and I have no problem
have you an idea of the problem something that don't like the battery disconnect/reconnect ??
thanks
and excuse me for my bad english but I'am french origin so it's not really easy for me
thanks
I have a little problem with my supercharged mx5 (t28 turbo kit)
last week I have an alarm problem and I disconnect the battery during one night
when I reconnect her the car don't run normally
the idle is unstable when the engine is hot
when it's cold the car is a 850 trs/min but move like an old V8 or like it's on 3 cylinder
and when it's hot the car stop immediatly if I don't leave my foot on the accelerator pedal
on boost all run good and I have no problem
have you an idea of the problem something that don't like the battery disconnect/reconnect ??
thanks
and excuse me for my bad english but I'am french origin so it's not really easy for me
thanks
MX-5 Lazza said:
Firstly your car is turbo-charged not supercharged. A supercharger is belt-driven 
Secondly, to have any chance of answering your problem we will need to know what is controlling fuel & timing. Do you have a piggy-back ecu like eManage or a standalone replacement ecu?
I run on the standard ECUSecondly, to have any chance of answering your problem we will need to know what is controlling fuel & timing. Do you have a piggy-back ecu like eManage or a standalone replacement ecu?
- mazda cosmo fuel pump
- fuel pressure regulator
- 1800cc injectors
So I guess that's an AFPR (Auxiliary Fuel Pressure Regulator) that is controlled with a vacuum pipe.
The 1.8 injectors will add more fuel but as you are using the stock ecu it will be running a bit rich a lot of the time. Should be fine though.
Your stock ecu will be controlling idle so as long as all the sensors are ok (TPS, O2, MAF/AFM) then the advice for checking your idle will be the same as it would if it were completely stock i.e. you need to check and adjust the base idle. Do you know how to do this?
Cleaning out the idle control valve using throttle cleaner could also help but as your problems started after disconnecting the battery I'd assume base idle just needs resetting.
p.s. Your English is a lot better than my French (and better than some of the English from British people on here)
The 1.8 injectors will add more fuel but as you are using the stock ecu it will be running a bit rich a lot of the time. Should be fine though.
Your stock ecu will be controlling idle so as long as all the sensors are ok (TPS, O2, MAF/AFM) then the advice for checking your idle will be the same as it would if it were completely stock i.e. you need to check and adjust the base idle. Do you know how to do this?
Cleaning out the idle control valve using throttle cleaner could also help but as your problems started after disconnecting the battery I'd assume base idle just needs resetting.
p.s. Your English is a lot better than my French (and better than some of the English from British people on here)
MX-5 Lazza said:
So I guess that's an AFPR (Auxiliary Fuel Pressure Regulator) that is controlled with a vacuum pipe.
The 1.8 injectors will add more fuel but as you are using the stock ecu it will be running a bit rich a lot of the time. Should be fine though.
Your stock ecu will be controlling idle so as long as all the sensors are ok (TPS, O2, MAF/AFM) then the advice for checking your idle will be the same as it would if it were completely stock i.e. you need to check and adjust the base idle. Do you know how to do this?
Cleaning out the idle control valve using throttle cleaner could also help but as your problems started after disconnecting the battery I'd assume base idle just needs resetting.
p.s. Your English is a lot better than my French (and better than some of the English from British people on here)
no sorry I don't know how to reset the idle control ??The 1.8 injectors will add more fuel but as you are using the stock ecu it will be running a bit rich a lot of the time. Should be fine though.
Your stock ecu will be controlling idle so as long as all the sensors are ok (TPS, O2, MAF/AFM) then the advice for checking your idle will be the same as it would if it were completely stock i.e. you need to check and adjust the base idle. Do you know how to do this?
Cleaning out the idle control valve using throttle cleaner could also help but as your problems started after disconnecting the battery I'd assume base idle just needs resetting.
p.s. Your English is a lot better than my French (and better than some of the English from British people on here)
skinny said:
connect up the grd and 10 in the little diag box when the engine is warm, then adjust the idle screw so it idles at around 850-900rpm. whilst you're there, if you have a timing gun, check the base timing too.
I'am sorry about my poor english but I don't understand this parts "connect up the grd and 10" and where is the diag box ? (it's the obd in the engine ?)and the problem at 950 trs/min the car don't stop but seems to run like an old v8 or on 3 cylinder...it run normally after 2000trs/min
What year is the car?
if its a mk2, removing the battery will have reset the fuel-trims (i had this on my car) and it needs to "re-learn" a few paramaters which it will only do by being driven around.
Its also possible that you have a fuel-pressure problem.. with a uprated pump, its been known that they can over-power the standard pressure regulator causing high fuel pressure at idle.
either way you need to see what your fuel pressure readings are.. does the pressure regulator installed have a gauge on it?
if its a mk2, removing the battery will have reset the fuel-trims (i had this on my car) and it needs to "re-learn" a few paramaters which it will only do by being driven around.
Its also possible that you have a fuel-pressure problem.. with a uprated pump, its been known that they can over-power the standard pressure regulator causing high fuel pressure at idle.
either way you need to see what your fuel pressure readings are.. does the pressure regulator installed have a gauge on it?
NeoVR said:
What year is the car?
if its a mk2, removing the battery will have reset the fuel-trims (i had this on my car) and it needs to "re-learn" a few paramaters which it will only do by being driven around.
Its also possible that you have a fuel-pressure problem.. with a uprated pump, its been known that they can over-power the standard pressure regulator causing high fuel pressure at idle.
either way you need to see what your fuel pressure readings are.. does the pressure regulator installed have a gauge on it?
it's a 1991 eunos roadster and I already do 200 miles with the car it's not differentif its a mk2, removing the battery will have reset the fuel-trims (i had this on my car) and it needs to "re-learn" a few paramaters which it will only do by being driven around.
Its also possible that you have a fuel-pressure problem.. with a uprated pump, its been known that they can over-power the standard pressure regulator causing high fuel pressure at idle.
either way you need to see what your fuel pressure readings are.. does the pressure regulator installed have a gauge on it?
if I remenber last week when I check the fuel system I read 5/6 psi but not sure
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