rough idle but no cel
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rough idle but no cel
hi, don't want to give up on my evo 4. it's a 98 lancer coupe with an evo 4 engine. tried almost everything and i couldnt find the reason for the rough idle. really hope someone from here could help.
#2
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maybe its the tune? have you tried getting it tuned.
my car used to have cold start issues and rough idle, i got it tuned and its fine now.
try doing a boost leak test aswell, maybe somewhere the car is leaking out vacume, that can cause rough idle aswell.
my car used to have cold start issues and rough idle, i got it tuned and its fine now.
try doing a boost leak test aswell, maybe somewhere the car is leaking out vacume, that can cause rough idle aswell.
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i already had it tested for vacuum leaks and still the rough idle exists. we swapped several parts as well just to check but to no avail.
swapped maf, throttlebody w/ servo, sparkplugs, plug wires and coil pack, fuel pump.
dont know what else to check.
#5
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thanks for your reply. how do i go about with the tune? can the stock ecu of an e4 be tuned?
i already had it tested for vacuum leaks and still the rough idle exists. we swapped several parts as well just to check but to no avail.
swapped maf, throttlebody w/ servo, sparkplugs, plug wires and coil pack, fuel pump.
dont know what else to check.
i already had it tested for vacuum leaks and still the rough idle exists. we swapped several parts as well just to check but to no avail.
swapped maf, throttlebody w/ servo, sparkplugs, plug wires and coil pack, fuel pump.
dont know what else to check.
you need ecuflash and a flash cable to tune your car. you can get it done locally if there are people in your city who tune evo's or get email tuned from united states.
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no I dont have one installed. but looking at my sparkplugs, i think am running lean. am planning to buy a obd 2 scanner
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i also had a compression test. 170, 150, 160, 150.
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#8
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firstly get a wideband and then go from there. see where your AFR's are and then proceed forward.
i dont think compression should have more that 15 diffrence, but im not sure.
im sure tuning will do the job because you did everything else, maybe a bump in timing or fuel will helpout.
i dont think compression should have more that 15 diffrence, but im not sure.
im sure tuning will do the job because you did everything else, maybe a bump in timing or fuel will helpout.
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firstly get a wideband and then go from there. see where your AFR's are and then proceed forward.
i dont think compression should have more that 15 diffrence, but im not sure.
im sure tuning will do the job because you did everything else, maybe a bump in timing or fuel will helpout.
i dont think compression should have more that 15 diffrence, but im not sure.
im sure tuning will do the job because you did everything else, maybe a bump in timing or fuel will helpout.
yes it should not go beyond 15 of a difference. so i have 2 cylinders that are too low.
damn cel wont turn on.
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#13
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Don't get hung up on the fact you have 2 cylinders are reading 15 psi lower than the others. Get a wideband and do some research on how to pull a datalog from your car. That will help point you in the right direction. Otherwise, like I said earlier, you'll be shooting in the dark. If you're not up to researching, have a competent mechanic take a look at it for you. We really can't do much here since a rough idle can be caused by lots of things.
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