Hey guys I need some help... I just went thru comp school this past weekend and I had a few problems with the car. Friday during the school the car went into limp mode the first time we did a rolling start so I duckd into the pits. We check plugs, wires and even snag the distributor off of chads street car (rotor screw had come out a buggered up the works in mine). Whats weird is no codes on the S300 even when the sel is on. So I get thru comp school and the race sat. Sunday car runs fine up untill the race. Sitting in grid the car throws a code. Shut it off then on and it seems ok. I'm P1 in the stinger race so I'm a little worried if this thing throw the code on the pace lap and goes into limp mode on the start. Sure as poop the pace car turns in to the pits and sel light comes on. Quick off/on on the key and nothing, so i trun down pit road. I stop at the end with the officials and one more time off/on and no light. So I get sent out at the end of the first wave. As soon as I get about 3 turns in the car hesitates and breaks up at 7K then clears up. I decide to take it alittle easy and stay out on track to see if it will clear up. And for come reason after lap 3 i was good. Whats weird is this time the sel never stayed on and when it hesitated the shift light and sel would flicker for a second or two and both go out. I'm assuming its a short some where. Any ideas would be a great help. My first thought is that it may have somethng to do with the wiring of the shift light, maybe a bad splice as it has to connect into the distributor to get its reading right? Anyway I figured I'd ask here first as there is always alot of knowledge in this forum.

Michael.

 

Do you have hondata or stock ecu? What code is it throwing?

 

also a note....

it did this with 2 seperate DISTRIBUTORS!

One of which was in my street car which I have not had any problems with........and I also have an S300 system.


Michael....i forgot to check your data logs....that might give us a clue....do you know how to pull those?

chad

 

Thought about that about an hour from home last night. I will try to make some time this weekend. This week looks a little busy at work but I will see what I can do.

 

Mike, I had a very similar problem and it wound up being my Hondata chip coming loose inside the ECU. Pushed it back in firmly and have had no issues since. I'm using S100, and I know the S300 is different, but I'd consider looking there.

You could also check all the grounds for proper resistance.

 

How do you check a ground for resistance? I will pull the ecu and check the chip.

Chad I'll let you know when I get my hondata software back from Kienan, get it loaded on my laptop and upload the data from the ecu.

 

i would also check that blue wire you tapped the tach from.

 

just dl it from hondata....then download to your laptop from ecu

 

Ok will do hopefully tomorrow or thursday.

 

Adam, I opened my ecu and the S300 has plastic pins that hold the chip to the board so everything was tight.

I'll check the grounds and the wiring for the shift light.
Thanx guys.

 

New update..
I checked all the connections under the dash. I found loose connections at the power and ground connections for the shift light, oil pressure light and oil pressure gauge and butt connectors in a number of places. The butt connectors were removed and loose connections were all soldered and shrink wrapped nice and neat. It appears the oil pressure light and gauge along with the shift light get power from a plug near the ecu location (brown plug / black wire). This connection was loose. Also the shift light seems to get its signal from the tach test connection. I soldered this connection as well. I started the car and let it run at ideal for 20 min while I cut my grass and no code and car ran great. Still looking for ideas so please let me know. Thanx for looking.

 

First of all, "limp mode" is a very specific thing with Hondata. Limp mode is a limit of exactly 4000 rpm. If it is revving past that it is not a problem with the computer period. If you are breaking up at 7000 rpm then it could be either a fuel problem (like a main relay beginning to fail) or an ignition problem further down the line like ignition wires or something to that effect.

Datalogging is KEY to figuring out problems, get used to pulling logs and always have a spare distributor if you're using a B.

sander

 

Thanx Sander, I was hoping you would pop in. The car did go into limp mode (will not rev over 4k) each day. With my dizzy and one out of chads street car. It had a break up at 7k for only the first 2 laps in Sundays race. Again what was weird was the shift light came on with the sel light in 2-3 quick flashes when it broke up then it ran fine. After looking at where the shift light gets it power and its signal has me puzzled as to why it would be lighting up at all with an engine breakup.
I hope to get some time on the dyno here in the next few weeks and maybe I can figure this out. Thanx again for the help and happy Easter gang.

 

Mike, good to hear on the chip socket. And sorry, I totally missed the earlier post about testing grounds. You'll need a multimeter with the sharp-pointy prong leads, set to read ohms. Touch one end to a ground on the chassis (note that paint will affect the reading, so you need bare metal), the other to an exposed part of whatever ground wire. The resistance should be very low (0?). Any high readings will indicate a bad or loose ground.

 

Testing grounds using an ohm meter is not usually a good indicator of anything. You'll have a reading of 0 ohms (good) if you have at least ONE strand of copper wire thats still connected.

ohms are better suited as a measurement value for internal resistance of sensors.

Just go around and make sure your grounds are clean and free of corrosion.

Also, the s300 unit can not pop out of the board like your chip had Adam. Mike, it is also possible on that note that you have a poor connection on the ECU board which would probably only be truly ruled out with a test ECU to use that is a known good unit.

 

Damn Casey's eyes! *shaking fist* Maybe that's why we couldn't figure out WTF was up with the Subaru

 

Thats what Hondata said too. I may have to send it down to chad to have him run it in his street car for a few weeks to test it. He beats the shniz out of his car so if its going to ack up it should do it for him :D