Vipec V88 engine cut

[Guest |304|]

We were running the v88 on a turbocharged 6 cyl engine at up to 1.3 bar and AFR 11.2- 12.0 for over thirty minutes and the engine quit like it hit a hard cut rev limit.

The throttle was lifted and the vehicle coasted to a stop. While it was coasting in gear the rpm was registering "60" rpm. The power to the ecu was then turned off and back on. An attempt to crank was made and the engine was

hydraulically locked with fuel. The plugs were pulled and the fuel flushed. The engine then started right back up. Then an attempt to retrieve the ECU log was made and there was no log at

all for this run but there were two older logs that we left there. The ecu is triggered to log at 1000 rpm and over btw. We don't think we hit any hard limits as they are 2.2 bar and 6500 rpm and we didn't run over 6300.

Does the ecu log all records at power down or as they are produced? Also does this sound like a loss of crank or cam sensor because of the "funnny" rpm while coasting?

Any insight would be appreciated as we have no logs on this one.

[rayhall]

The ECU logger at the moment only allows ten data logs. If you have the logger turning on at 1000 rpm then it will take no time to have ten logs. I would turn the logger on at much higher rpm or use an external switch.

The fuel in the cylinders can have only come from the injectors being held open for some reasion. Was there more then one cylinder with fuel.

Ray.

[Guest |304|]

All cylinders had fuel. We were also running with the thermostat out in an experiment to test oil/air cooling.

From a separate engine log box (all it had was map, coolant temp, oil pressure, oil temp) we also noted that the

coolant was around 137F at the time but had been higher earlier while we were running at higher power.

We were also running closed-loop afr control and it was very cold outside. One theory was that the coolant temp fell underneath the ECT cutoff for lambda/afr control, causing the engine to quit, and then while coasting it thought it was in crank enrichment and flooded. One driver has also just reported that one time he loaded the engine around 3700 rpm while not fully warm and it did the same thing. At the time we thought this was a bad ECU and put in another one. I now think that it was not the ECU but rather some kind of unique

combination of factors we set in the config that conspired to cause the cut and subsequent flood. I can PM the config

if you want to see it.

As for your question about the logs. We just had two previous logs on it I think but I will double check. Did you say that the box logs

as it goes, or collects in RAM and dumps? I have seen vendors do it both ways.

Thanks again,