Odd Problem - RPMs Drop 3500 and can't accelerate
05-19-2016, 02:19 PM
#1
Odd Problem - RPMs Drop 3500 and can't accelerate
Hi! Forgive me if this is the wrong section, but I believe that you guys would have the most relevant knowledge on a problem such as this.
I'm running a P75 OBD1 Manual ECU, B20B, Hytech header, adjustable FPR, and a short intake. My Distributor is 1 year old, but hasn't seen much use, new 1 MFR, new NGK plugs and wires. Baffled Moroso pan. I've traced my grounds and they seem fine. This is all in a 92 GSR.
I was at the track (road racing), and the car would randomly put itself into what seems like limp mode. It would just lose all power, no acceleration, no response from the pedal. Once it slowed down it would either recover or buck violently. My VSS is not connected because it's mechanical and it blew apart. The only other issues is the ELD code, which is standard with this chassis and newer systems. Additionally, I tried with a full tank as opposed to a half tank to ensure I wasn't starving. Does anyone with knowledge of the ECU know whether the VSS would cause this? I know that the VSS is required for vehicles that are vtec equipped.
Thanks for any insight that you can shed on this!
I'm running a P75 OBD1 Manual ECU, B20B, Hytech header, adjustable FPR, and a short intake. My Distributor is 1 year old, but hasn't seen much use, new 1 MFR, new NGK plugs and wires. Baffled Moroso pan. I've traced my grounds and they seem fine. This is all in a 92 GSR.
I was at the track (road racing), and the car would randomly put itself into what seems like limp mode. It would just lose all power, no acceleration, no response from the pedal. Once it slowed down it would either recover or buck violently. My VSS is not connected because it's mechanical and it blew apart. The only other issues is the ELD code, which is standard with this chassis and newer systems. Additionally, I tried with a full tank as opposed to a half tank to ensure I wasn't starving. Does anyone with knowledge of the ECU know whether the VSS would cause this? I know that the VSS is required for vehicles that are vtec equipped.
Thanks for any insight that you can shed on this!
05-20-2016, 10:54 AM
#3
Re: Odd Problem - RPMs Drop 3500 and can't accelerate
Yes, apologies for not mentioning that. I had a second MAP sensor and tested with it under the same conditions the next day at the track and the same thing happened.
Thanks for the response. I'm hunting for anything...
Thanks for the response. I'm hunting for anything...
10-09-2016, 05:09 AM
#5
Re: Odd Problem - RPMs Drop 3500 and can't accelerate
Figured I'd come back and post my fix for *this* problem. (Upsets me when I find similar results to a problem and no one ever mentions a fix) I went out to the track and the card ran well with this fix. One modification I didn't mention was that I have a 7lb flywheel as well so I could imagine the ECU might not be happy with it dropping revs so quick.
Yes, the VSS was a problem. Obviously, I could have bought the proper speedometer cable for this application, but I did that once and it shredded. Anyone who knows the EF/DA chassis knows that the speedo cable can be an issue. Since I don't really need a speedometer because of the magic of data acquisition systems, I didn't mind losing mine.
The fix:
Found a cheap VSS. $11.88 The one that would bolt to my transmission (YS1 Cable case) was a VSS as described:
Honda L4 1.6L (Engine ID B16A2, D16B5, D16Y5, D16Y7, D16Y8) with Manual Transmission
Fits Nippondenso Style
- Application:
Honda Civic 1996-2000
HONDA CIVIC DEL SOL 1997
Bought the necessary pigtail /$4.96), wired power in, grounded and attached the signal right into the ECU. This would be Pin 10 on the B connector of the ECU. Colors may vary: yellow/blue or /orange
Next step might be to get an electric speedometer, from an integra or whatever is cheap, and do that unless I come across a nice Stack gauge panel.
Yes, the VSS was a problem. Obviously, I could have bought the proper speedometer cable for this application, but I did that once and it shredded. Anyone who knows the EF/DA chassis knows that the speedo cable can be an issue. Since I don't really need a speedometer because of the magic of data acquisition systems, I didn't mind losing mine.
The fix:
Found a cheap VSS. $11.88 The one that would bolt to my transmission (YS1 Cable case) was a VSS as described:
Honda L4 1.6L (Engine ID B16A2, D16B5, D16Y5, D16Y7, D16Y8) with Manual Transmission
Fits Nippondenso Style
- Application:
Honda Civic 1996-2000
HONDA CIVIC DEL SOL 1997
Bought the necessary pigtail /$4.96), wired power in, grounded and attached the signal right into the ECU. This would be Pin 10 on the B connector of the ECU. Colors may vary: yellow/blue or /orange
Next step might be to get an electric speedometer, from an integra or whatever is cheap, and do that unless I come across a nice Stack gauge panel.
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mikej94civex
Honda Civic / Del Sol (1992 - 2000)
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