Hello,

I am in Orlando, FL. I have a chipped P28 ecu for my GSR swap to accomodate the skunk2 intake manifold, headers, exhaust, secondaries and knock sensor. Apparently, the ECU was tuned with launch control enabled and I can't get my car to run right because I don't have a clutch sensor.

Is there anyone that can disable the launch control for me? I don't have an eprom reader.

 

What program are you running? What clutch sensor?

 

The previous owner said it was Crome. As for the clutch sensor, I am referring to the sensor on the pedal. I believe the launch control looks for this and since I don't have this sensor, it is messing with my throttle. I hit a rev limit of 3k rpm when in neutral and I rev. While driving, it tries to stage at 1,500 RPM

 

Launch control is disabled by speed. It has nothing to do with your clutch input. Crome does not even support clutch input like other better EMS.

 

Ok, so are you saying that I just have to drive the car so that launch control gets disabled? I am not sure I understand what you mean by "Launch control is disabled by speed". Do I pretty much have to ride my clutch past 1,500 RPM each time to bypass the launch?

Either way, is there a way to just disable it or at least for me to know how to use it? When I had launch control on my Subaru, it worked with my clutch input. It was wired directly to trigger it as well as the ECU to receive engine speed input. The clutch input was used to activate the control. I guess it does not work the same on these chipped ECU?

 

First things first, What's wrong with your car? What are your issues.

When he says that launch control is disabled by speed. Most tuners have launch control set so that if your vehicle is going over a preset speed, lets say 5mph, launch control would be disabled. Lunch control is usually only enabled when the vehicle isn't moving.

Launch control really shouldn't do anything to hurt daily driving. Unless whoever tuned your EPROM was completely F#@Ked up and set it so that you need to be moving over 10-20mph!

If you don't have an EPROM reader than I'm guessing that you have no way to write to an EPROM chip. Are you looking for someone to send you a new chip? That will probably cost ya!

 

GhostAccord,

Thanks for your reply. Here is the run down of everything:

1992 honda civic. The car had a B18A1. While the engine was in the car, I had a check engine light on throwing a code 14. I took out the IACV and the FITV off and cleaned them well. Still same issue, replaced them both two times, still same issue. Replaced TPS and MAP twice as well, still same issue. I used propane to check for vacuum leaks, still same issue. At that point I said, screw it cause I am going to swap the motor out in a few days.

Now, I swapped the LS out for the GSR, still same code 14. I replaced all sensors and cleaned them all just as I did with the LS and still same code. I reset the ECU by removing the backup fuse as suggested, still same issue. I tested the TPS sensor for both voltage and continuity and the readings were fine. 5v for voltage and .5v for closed throttle and 4.60 for WOT. I thought it could be a wiring issue since the issue replicated with the new engine but turns out I get really good signal to the sensors.

I checked for vacuum leaks on the new GSR and everything is OK as well.

Now, I have two issues that could be related or not. First, we have established the code 14. The second issue is that with the chipped ECU, once I start driving, as long as I am under 1,500 RPM, the car is smooth and as soon as I hit 1,500 RPM, it jerks violently. Once I get over the 1,500 RPM hump, it's smooth again. So, this is obviously brutal for local traffic and take offs from a dead stop. I pretty much have to ride the clutch past 1,500 RPM to get over that hump. It's almost as if it gets stuck there. At first I thought it was the launch control since I didn't have a clutch pedal sensor but appears it reads of VSS so there goes that thought.

Now, if I put the stock LS ecu, which I had before, I don't get the 1,500 violent jerks and the car is very smooth and not rough at all. However, my code 14 is still there on either ECU.

Based on this analysis, I am thinking there is something wrong with my map? Maybe too much fuel around that RPM?? If that is the case, I would need a tune. The reason I have it chipped is because it came this way to eliminate the knock sensor cel, secondaries, incorporate a better fuel trim with the skunk2 manifold and headers and exhaust.

What do you think? What can I do at this point?

 

Fix the IAC valve issue with the stock ECU. Then try your chipped ECU. Best to have it tuned also. I have run Honda's with the IAC valve unplugged so I highly doubt that is causing your 1500 hiccup. But you never know......

 

The problem is that I have tried fixing the IAC code 14. I haven't been lucky. I tested and replaced the following more than once: IACV, TPS, MAP, bleed air from the coolant system, checked for vacuum leaks.

I don't know what it could be especially if I am getting the correct continuity readings and voltage. Is there a device I can purchase to read precise issues instead of just code 14. For example, anything that can tell me exactly what is causing code 14?

 

Have you tested the wiring harness between the IACV and the ECU?

 

Any pointers on how to test this one? I know that for the TPS I test the red/middle wire for continuity and the yellow wire for voltage with the ACC set to ON while the car is off. What about the IACV? How do I test for that?...is it a similar process?

Thanks for your help

 

This is incredibly common to mix up.

Check that your IACV wiring is BLK/BLU and YLW/BLK, if it isn't then you have something plugged in wrong.

If they are, the easiest way to check it like this.

Yel/Blk should have 12 volt power with key on.

Blk/Blu should have continuity with pin A9 at the ECU.

 

You are correct!!!

I had the same suggestion at the PGMFI.org forum. Here is what I discovered:

WOW!! I could not help but to check tonight. You got me thinking about those wires. So, apparently, I had the wrong connector to the IACV, which explains why the new swap inherited the same issue. Here is what probably happened. The engine harness for that car had a lot of connectors that were loose and ready to fall off. I fixed the obvious ones through inspection. Since the LS didn't require the purge solenoid connection, the wire connector clip was just hanging (I didn't know that). So, I am assuming that some time ago, the real IACV connector broke off and I didn't notice it broke off so when I was changing the head gasket about a year ago, the only remaining visible connector was for the purge solenoid so I assumed it was the correct wire/connector because one of the wires for it is also yellow/black just like the IACV wires where one of them is also yellow/black.

In other words, the broken connector for the IACV went unnoticed because it sleeved itself back into the wire-loom of the engine harness during the head gasket replacement leaving just one connector exposed, which turned out to be the purge connector clip in which one of the wires is also yellow/black (which can trick you into thinking it is the IACV connector)

It's late in the night to fix but I am positive this is the issue. I will fix this tomorrow and HOPE/PRAY that when I fix this and the CEL goes away, that the chipped ECU doesn't still have that 1,500 RPM jerking issue.

I will keep you posted.

Thanks soooooo much for the help. I have been dealing with this for a week and I am sure how you can see why it went unnoticed...the correct wires with the missing clips were hiding in the wire-loom!!

 

OK, that was it!!....the broken wires that were just hidden were actually part of the missing clip from the IACV...that solved ALL issues: bad idle, check engine (code 14) and rough and violent jerks of the engine. The car runs strong and very, very smooth!!! Another successful swap (after so many years) :D

Thank you all for the help