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IBALLHARD
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Discussion Starter · #1 · (Edited)
my car just went into limp mode tonight..(wont rev past 4k)
and there is no CEL on whatsoever, what i gathered from searching is maybe my ECU went bad?

i have a p28 with hondata s300...

it will start up AND idle normal....
oil level is fine, timing belt tension seems fine...

let me know if you need any more info on anything....
but it seems to be running normal just wont go past 4k...

any input?
 

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IBALLHARD
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1,461 Posts
Discussion Starter · #3 ·
hmm...
maybe i never thought of that...
i will be pissed if it is... its only like a year old and its a magnaflow 3 inch high flow cat...

how would i be able to actually tell if it is blocked up?


any other thoughts on what the hell this could be?
i need to fix this asap.
 

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hmm...
maybe i never thought of that...
i will be pissed if it is... its only like a year old and its a magnaflow 3 inch high flow cat...

how would i be able to actually tell if it is blocked up?


any other thoughts on what the hell this could be?
i need to fix this asap.
If the cat is blocked, it will be very very hot... Ron
 

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hmm...
maybe i never thought of that...
i will be pissed if it is... its only like a year old and its a magnaflow 3 inch high flow cat...

how would i be able to actually tell if it is blocked up?


any other thoughts on what the hell this could be?
i need to fix this asap.

my bad. i assumed you had a stock cat. a high flow cat most likely wouldnt be blocked.
 

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maybe your cat is blocked up? cuz i thought limp mode was 3.5 rpms
When i fried my ECU it revved to 3.5rpms and also the CEL was solid. When i say solid, it clicked on when i turned the key to "ON" and never went off. You might want to PM motoman about this he is the ECU/tunning guru here.
 

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jump the service connector with the ignition on, see if the cel comes on solid, or blinks at all, or doesnt come on at all.

if the cel comes on solid, it means there are no codes, and everything electrically is fine.
if it blinks, it has codes of course lol
if it doesnt come on at all, it means either the bulb is blown or the ecu has an issue (aka code 0)

it is possible that the cat is clogged.
to check for that, just unbolt the exhaust before the cat, let the car warm up fully in your driveway or whatever, then take it for a spin around the block and see how it acts. if it revs fine unbolted, then the cat is prob clogged.

you can also connect a laptop to the ecu and turn on the datalogging and it will tell you if you have a cel or not and what the codes are.

where did you get the ecu from?
 

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also, do you have launch control activated? maybe the ecu isnt seeing a speed signal, in which case launch control would be in effect at all times
 
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