Strange bogging down on Startup
We've noticed a strange issue that our Exy (T30 Series 1) is having and am hoping someone might know how to go about fixing it/finding the problem.
When the car starts up and we drive it without letting it warm up, it bogs down a lot when I change gear.
I think it occurs when I accelerate, release (the accelerator and any engine load, i.e. clutch in) and then get back on the accelerator (about 1 second after I get back on the throttle, it bogs). Its quite significant and seems to be the same drop in performance regardless of RPM.
Although at low RPM/throttle position it goes from accelerating to decelerating and at high RPM/throttle position it goes from a rapid acceleration to a slow acceleration.
It goes away after the car warms up but it does do this on warm startups occasionally.
On a side note, we have the full Hi-Tech exhaust - Extractors, high-flow cat and cat back
It seems to be an electronic thing, either a sensor giving false information or the ECU itself trying to maintain "safe" operating conditions. I've dug around the Workshop manual and couldn't find much other than the following:
At startup, the ECU runs the car rich - injecting fuel twice in each cylinder per engine cycle
The MAF sensor influences the fuel input
The O2 sensor in the Hi-Tech extractors influences the fuel input
My initial thoughts were that it might be fuel delivery related, that it might be build-up around the O2 sensor in the exhaust giving false information or the ECU having "learnt" something in order to keep the engine "Safe".
That's all I can think of and I can try to film it because it does do it consistently on cold start-ups if that helps. Apologies for the essay...
Adrian, Guildford NSW
Black 2002 T30 Series 1 Ti
Member No. X-4675
2/Mar/2018, 12:49 pm
Re: Strange bogging down on Startup
Being an 02 T30 I'm assuming it has done a few kms. Has the O2 sensor been changed or the MAF cleaned ?
Kev X450(c) T30 Guru
03 Titanium Ti T30 Series 1 **MODIFIED**
My CarPC Worklog
2/Mar/2018, 1:26 pm