Rev cut off at 4 K???

[Ep3 ked]

Now that I have the Ep back in action my rev limit is at 4 K its not fun not being able to hit vtec.. I checked my ECU I dont have K PRO so what should I do? I used to be able to rev that shit up to 8k ! What can I do to get it back??????

[acu210]

check oil

[yyi]

you're probably in limp mode. and you do hit vtec at 2.2k, assuming you are on your stock motor

[MajorJones]

i had the same but i would only go up to 3.5k. If its what i think it is just unplug the main wiring harness on the ecu count to 3 Mississippi and plug it back in and bingo all normal again.

[shanewdude]

i had the same but i would only go up to 3.5k. If its what i think it is just unplug the main wiring harness on the ecu count to 3 Mississippi and plug it back in and bingo all normal again.

Before you reset that ecu, you might want to find the code it's throwing or find out why it's in limp mode in the first place.

[Ep3 ked]

oil is good and clean I all ready unpluged the ecu still same rev limit the only code im throwing is for the air temp thats in the air intake..

[the1986]

The same thing happened to me the other day after i cleaned my air filter. I noticed that my airbox was a little loose, so i re-installed everything snug and reset my ecu and I've been fine.

[BlownSi05]

What was done to the car? Need some more info to help you out.

When I put the had back on the motor after pulling it, I forgot to plug in the VTEC solenoid on the back left side of the motor, which kept it in limp mode.

Edit: Doh....just saw that you were throwing a code for AIT.....reading fail on my part.:mredface:

[Deadphishy]

You/we need to know more about your car. Hitting 8k in an EP is very concerning, the Tach in the EP is known to be off. When the Gauge reads 6k your motor is spinning closer to 6.3k or 6.4k. So when you hit the factory fuel cut at 6800 Rpm the tach might jump all the way to 7200.

The motor actually does go to 8k, you very well might have a Hondata Flashed ECU. Hondata flashed ECU's move the Fuel cut to 7500Rpm making your tach read close to 8k.

Like stated before, You do not have the same Vtec that the B series or even the k20a2 has. You have a system designed to improve low rpm emissions, not to increase Tq or power.
Vtec Hits on a k20a3 at 2200 Rpm

as far as the 4k rev limit. That is limp mode.

The ECU has found something wrong or something isn't right, so to protect itself the motor imposses a very low Rev limitor. This is Very often cause by low Oil levels, or a bad sensor/connection.

[kenscivic]

You/we need to know more about your car. Hitting 8k in an EP is very concerning, the Tach in the EP is known to be off. When the Gauge reads 6k your motor is spinning closer to 6.3k or 6.4k. So when you hit the factory fuel cut at 6800 Rpm the tach might jump all the way to 7200.

The motor actually does go to 8k, you very well might have a Hondata Flashed ECU. Hondata flashed ECU's move the Fuel cut to 7500Rpm making your tach read close to 8k.

Like stated before, You do not have the same Vtec that the B series or even the k20a2 has. You have a system designed to improve low rpm emissions, not to increase Tq or power.
Vtec Hits on a k20a3 at 2200 Rpm

as far as the 4k rev limit. That is limp mode.

The ECU has found something wrong or something isn't right, so to protect itself the motor imposses a very low Rev limitor. This is Very often cause by low Oil levels, or a bad sensor/connection.


Listen to this man. When a vehicle goes into limp mode the computer has found something possibly catastrophic wrong and it is giving you enough revs to get home/ to a shop to get it fixed.

[Ep3 ked]

Hum very helpfull !! I just unpluged the main on the ecu for 3 sec. and the rev limit was gone as well as the CEL (of corse) but as soon as the CEL comes back on the rev limit is back on. Oil is toped off and clean. I could kinda feel the diffrence in power when the CEL and the rev limit was off. The only code im throwing is for the air temp sensor. ? I had to replace the head gasket and new valves where put in.The car only has like 68xxx its driving great other then this problem.. It just seems kinda slower then it should be on the low end :mfrown: I have full exhasut and high flow cat with a CAI Koyo rad.and cosmetic head gasket

[civichbsi209]

possible problem with map sensor?

[Ep3 ked]

possible problem with map sensor?
Just replaced it. the idel rev is perfect

[Deadphishy]

You shouldn't be driving the car the way it is. The rev limitor is there to tell you something. "FIX ME ASAP"



Did you replace the AIT sensor?

[Ep3 ked]

no not yet.. I dont think that it would cause this.. idk.. the car seems to be running to well for it to be somthing crazy wrong.

[Deadphishy]

no not yet.. I dont think that it would cause this.. idk.. the car seems to be running to well for it to be somthing crazy wrong.

I would start there

[Ep3 ked]

I replaced the IAT today and cleared the ECU. Still having the same problem. I guess that the IAT is a big deal with the PGM system so Im glad I replaced it anyways.. I checked out the VTEC solenoid in the back to make shure the plugs had good contact. One of the male prongs was bent so I think that could be it.. wish me luck .

[Ep3 ked]

**UPDATE** Found out the problem my cat isnt heating up right. It might be cloged to. I have a uni. high flow cat. Its not so bad where I cant drive it or anything its a very suttle dif. So what I did was put in this stuff called 911 for diesel fuel lines that freeze up. Its prette much alcohol I put half the bottle in and filled my car up the rest of the way with 93 octane. Im going to just go on a really long car ride till its empty and do it again in hopes that it will clean it out.. Everything checked out fine other then that, no codes or anything. ! :msmile:

[Ep3 ked]

Also the OBII was poping up the EGR valve .. Where is that located, on the TB? Do we even have a EGR valve?

[iDom]

I have an intermittent check engine light that causes a limp mode at 4k, just like this. But mine is code P1259 which is a VTEC System Malfunction.

[Deadphishy]

I have an intermittent check engine light that causes a limp mode at 4k, just like this. But mine is code P1259 which is a VTEC System Malfunction.

Check your Oil level, check your clips, Check to make sure the Vtec screen isn't dirty.

[iDom]

Check your Oil level, check your clips, Check to make sure the Vtec screen isn't dirty.

I have done all that, and have also gone as far as checking the continuity on all the sensors too, I am clueless as to where to go from now besides a dealership..

Taken apart the VTEC Solenoid (twice).
Changed oil, levels were perfect, still came off and on.
Checked for continuity on the sensors, all checked out.. Still getting a P1259 code and limp mode.
Screen is clean, no clogged ports, idk.. I hope it's not the ECU or a faulty wire SOMEWHERE in the system.. (These were other 'possible' causes that I came across doing my research)

[Ep3 ked]

I have done all that, and have also gone as far as checking the continuity on all the sensors too, I am clueless as to where to go from now besides a dealership..

Taken apart the VTEC Solenoid (twice).
Changed oil, levels were perfect, still came off and on.
Checked for continuity on the sensors, all checked out.. Still getting a P1259 code and limp mode.
Screen is clean, no clogged ports, idk.. I hope it's not the ECU or a faulty wire SOMEWHERE in the system.. (These were other 'possible' causes that I came across doing my research)

Def. sounds like a bad connection or somthing of that nature. I thought my clips where in snug and had good contact at the VTEC solenoid but I took a close look at the male prongs and one was bent checkem out ..

[iDom]

I inspected all of it, I actually still have pictures of all my stuff that I took apart, they all appear to be fine. That's why I'm just scratching my head cause I have no idea what's wrong with it. Pissin me off, that's a fact..

I don't wanna replace the entire assembly for nothing, I just need a professional to run diagnostics and HOPE that they give me the correct diagnosis so I can go from there..

[iDom]

Stealership wants like 100 bucks to do it, might have to just bite the bullet..
:squint:

[Stanz0r]

Sounds like a bad pressure sensor.

[Ep3 ked]

Sounds like a bad pressure sensor.

I had a bad oil pressure sending switch and the only thing it did was throw the dummie light on. I would give it a oil pressure test if it looks good I would jus take it to a pro..

[Deadphishy]

do you have any friends with a k series that you can steal the VTEC solenoid from. Slap it on your car and see if it works? if it does then you know what you have to replace.

Where in Ohio? i know a few people on here are from OH.

[iDom]

Fremont, OH. Very close to Toledo which is very close to Detroit, I'm sure you know haha.

But, no I actually don't. I have friends with B series, F series, and D series Honda motors lol.. And a friend with a DSM that doesn't run, naturally.. :mbiggrin:

[Deadphishy]

I wonder if Pure tuning will be able to help you out at all. They might have some used K series parts sitting around. I know i have an extra one or two, but i don't know if they work. My wife is pretty done with me working on my car at the moment. I spent about 5 days in a row working in the garage untill 2 am. because of our schedules we didn't see each other, awake that is, for about a week :P So maybe next week i'll be able to help you if you can't get this figured out.

[iDom]

Thanks a ton man that would be awesome. I only have 2 more payments on my car and it's paid off, so then I'll be able to start 'revamping' it.. Previous owner of the car molested it quite heavily with eBay garbage.. Putting new suspension on it next weekend actually. New exhaust soon, then I wish to get the halo headlights off and get some OEM headlights or something.. All in all, she's not bad for 160k on the motor and body being a daily driven Ohio car, and surviving a hail storm about 3 months ago lol.