Hondata

I tried changing my spark plugs, my old ones were heated up due to a clogged fuel filter a few months back. So far no misses in day and half about 100+ miles of driving. This would mean the obd1 ecu is more sensitive than the obd2 computer. I will give you guys an update and try uploading my data logs again.

^ good stuff, let us know how it turns out.

I have been determined to log the problem and finally have some evidence: (i didn't want to start a thread on the same topic)

This is the problem I am having, VSS drops to zero in a matter of less than half a second then returns to be fully operational. There is simply no way that my car is fast enough to go from zero mph to 54 mph in a matter of half a second. Additionally, alternator control turns on in this time frame of half a second and the gear sensor drops from fifth gear to first gear; in reality, during this time frame, I held the car in fifth gear the whole time but the datalog does not agree.

Is this an electrical problem or mechanical? I am really leaning to think that my VSS is bad. But someone says it could be my transmission or distributor? I hope not. Lastly, you see the AFR’s spike to 11s (the evidence is half a second late due to the AEM wideband datalogging speeds) which makes for that jerking motion that I feel briefly.
Any advice is appreciated guys!

no screenshots. You must post your calibration and a datalog showing the problem.

Yeah I had the same problem but worst my engine shutted down completely! =[ I pulled over than putted my stock ecu the car drives fine now.. any idea?

Spunkster wrote:no screenshots. You must post your calibration and a datalog showing the problem.

not a problem, here is the calibration and respective datalog:

In that datalog I do not see anything drop out except the speed, which leads me to believe there is a problem with either the speed sensor or the wiring that goes to it. This does not look like a power cut to the ECU.

diSTiNCt wrote:

Spunkster wrote:no screenshots. You must post your calibration and a datalog showing the problem.

not a problem, here is the calibration and respective datalog:

Mine did the jerk thing again this morning. Also with mine it will do the same thing it shows my speed drop the gear change, im almost curtain today I heard the relay kick off the fuel pump. When I run my stock obd2 ecu this weird problem goes away. Is the obd1 ecu thats more sensitive than the obd2 ecu?

I called hondata up, and the tech suggested trying the ecu on a obd1 car without the adapter harness.

Spunkster wrote:In that datalog I do not see anything drop out except the speed, which leads me to believe there is a problem with either the speed sensor or the wiring that goes to it. This does not look like a power cut to the ECU.

Exactly - speed sensor droping only while jerk! And this happend only with 1.4.3 - 1.4.5ver. software. I haven't jerks after I rollback to 1.4.2ver.
Look at this:
http://www.hondata.com/forum/viewtopic. ... 1916#41916

Why in one of the datalogs does the ACCL input go from on to off when this occurs?
What do you have connected to this output?

met wrote:Mine did the jerk thing again this morning. Also with mine it will do the same thing it shows my speed drop the gear change, im almost curtain today I heard the relay kick off the fuel pump. When I run my stock obd2 ecu this weird problem goes away. Is the obd1 ecu thats more sensitive than the obd2 ecu?

I called hondata up, and the tech suggested trying the ecu on a obd1 car without the adapter harness.

Im not sure, that was whiale I was crusing if you see my speed it never changes. I live in flroida, this was on i10 on a strait flat section of highway the only hills are very small overpasses.

How could I could roll back my software? I heard its not safe to do that?

Im open for suggestions, im compltely open to the fact it might be somehting in my wiring.

I tried finding the older version : viewtopic.php?t=9533&postdays=0&postord ... ta&start=0

but the download is no longer hosted, can you guys post this older version? I'd like to see if my problem goes away if I switch to the older version.

I noticed this problem with my car also about two weeks or so ago I even bought a new 4bar map sensor b/cause I thought it was the problem,its after putting the new one in and then changing to a stock map I found out that it was'nt the map I even changed my fuel pump,but it still does it randomly while driving.I have another system for my car(non-hondata) I will install that one test and report back.

The ECU is resetting itself. The ALTC, speedo and everything else are symptons of the reboot. This can be caused either be a bad vehicle wiring or main relay interrupting the power to the ECU, or something in the ECU code triggering it to reboot. In the case of the later, narrowing down the conditions which cause this is the important first step.

Hondata wrote:The ECU is resetting itself. The ALTC, speedo and everything else are symptons of the reboot. This can be caused either be a bad vehicle wiring or main relay interrupting the power to the ECU, or something in the ECU code triggering it to reboot. In the case of the later, narrowing down the conditions which cause this is the important first step.

Alright, I will start by checking my grounds then I will try a main relay. I'll keep you guys posted.