Didnt know what to title this, because I dont really know whats happening,
I have a 1993 Civic with a b18c1 and chipped p28. Ive had the car for 6 months and when I bought it, it had the rev limiter set at 9000 rpm. Last week or so I was making some pulls and it would only rev up to 7000 rpms before cutting off until it went back down to around idle rpms. It will always go back down to 1000-2000 rpm before I can do anything, even if I am keeping the pedal down the entire time. After it goes down it will drive like normal again.
Has anyone heard of this before? I have no idea what could be causing it to do this. I ran the computer for codes and got 06 Ect Sensor Circuit, 10 IAT Sensor, and 17 VSS Circuit Low Input. I replaced the ECT sensor because ive heard it can cause this and still have the issue.
I rarely rev this thing out but if there is a problem Id like to have it solved.

 

There is a shared ground for all three of those sensors... I would check that green/white wire and make sure there are no breaks/short-to-ground in it.

 

I was clarifying that those are the only things that the computer says have issues, I don't care about them if they don't fix my problem with the limiter. Will check those wires though.

 

Your problem is likely failing capacitors inside the tachometer (in the instrument cluster) making the tachometer read low... however, when you get the codes that you have described above, there is a possibility that your engine computer is protecting the engine by limiting the maximum engine RPM. Some call this "limp mode".

 

I was wondering about the limp mode, but I haven't seen anyone talk about it limiting all the way at 7k. The tach I am confident in it being accurate, because I can hear my vtec actuate at 4400rpm and can hear the secondary runners open at 5700rpm. The motor also doesn't sound like it's at 9k when the limiter kicks on.

 

You are still using a stock GSR intake manifold AND revving the engine beyond 9000 RPM ?

 

No, the motor is somewhat built, I've only hit 9000rpms once and never while making a pull, it doesn't have a stock intake manifold or headers

 

No codes for me but have the same prematurely hitting my limiter at 7k instead of 8k

 

Datalogs are your friend

 

I have that 4 pin connector on the ecu to hook up to but I've never datalogged or done any tuning myself.

 

Sounds like you have a reason to learn then. If you could peek at what the ECU is seeing and thinking, it would probably help determine what's not working right. I don't know how many times datalogs have helped me solve something that would never trip a check engine light. Like an intermittent faulty TPS sensor. Or a wonky map sensor. Etc.

The first question is, what was it tuned with (Crome, HTS, Neptune, something else)? Second question is do you have the USB->TTL adapter cable?

 

If you don't have the stock intake manifold, how do you hear the secondary runners engage at 5700 RPM ?

 

I do own the cable to hook up to it. I have no idea what it was tuned with previously.

 

It's still a gsr with an intake made for a gsr, there's no reason they shouldn't work

 

Without knowing what it was tuned on you may not even be able to datalog. You'll have to try all the old tuning softwares to try to figure it out. Or do some geek stuff, read the protocol information and figure it out that way.

Maybe it's time to get a standalone ecu. Winter project. Retune.