VEMS Community Forum

VEMS => Calibration & Mapping => Topic started by: Seight-v8 on September 21, 2013, 02:29:45 PM

Title: oscillation on idle after throttle close
Post by: Seight-v8 on September 21, 2013, 02:29:45 PM
hello all,

so my new injectors are in, upgraded to bosch red devils, 24lbs imported from America, 4 hole technology, a vast improvement to my 25 year old lucas ones in my V8.

Running is far better, smoother, low throttle is excellent, sound is superb.

But I have gained a small oscillation when coming off the throttle and it closing, causes a oscillation in the revs & lambda readings still it smooth's out a few seconds later.

lambda readings go from 0.71 to 1.17.....up and down till its finally smooth's out to 0.92, takes about 8-10 seconds to be back to normal.

I am thinking my injector settings are causing this, but any suggestions are welcome.

I really think I have hit the limit of my knowledge here and its time to look for someone to sort it once & for all.

cheers

scott
Title: Re: oscillation on idle after throttle close
Post by: gunni on September 21, 2013, 04:48:50 PM
Did you properly setup your new injector dead times? That sounds like the most likely proplem.
Title: Re: oscillation on idle after throttle close
Post by: Seight-v8 on September 21, 2013, 07:09:47 PM
I thought this might be the problem, I started with 200ms in the settings, but the surges were terrible, the engine almost dies when I use this, only when I got to 1600 did the surging die down to the lowest level I could find.

Looks like my knowledge has ran its course and I need someone who can do all the fine tuning.....I've tried and I can finally drive my car, but I know it needs more than I can give and I have to admit defeat.

its now over 3 years since I built the engine and only 500miles to show for it......its time I need to move on and use it....

I am sure for most people on here its an easy fix, but I just don't know enough to be able to give it justice.

if anyone can suggest any UK base help, then please do so.

thanks

scott
Title: Re: oscillation on idle after throttle close
Post by: dnb on September 23, 2013, 08:09:16 PM
I can supply my out-of-date limited knowledge if you are near the south coast and think it might help.  Do you have a datasheet with the injectors?
Title: Re: oscillation on idle after throttle close
Post by: Seight-v8 on September 27, 2013, 07:11:23 PM
thanks dave, but that's such a long way for me to travel in my car with no roof.....lol...

injectors are bosch 0280 156 013, I have a data sheet but nothing about opening times on it....

I think maybe if I got my hands on a pc oscilloscope I could trouble shoot a few problems better......I don't want to waste money here though if its going to be no good or use.

cheers

scott
Title: Re: oscillation on idle after throttle close
Post by: gunni on September 28, 2013, 12:58:05 PM
Where are you based? I´m in the UK
Title: Re: oscillation on idle after throttle close
Post by: Seight-v8 on September 29, 2013, 12:23:59 PM
hello,

I am in the north east of England, about 20mins from Middlesbrough & darlington....

cheers

scott
Title: Re: oscillation on idle after throttle close
Post by: Erikk on September 30, 2013, 07:57:42 AM
I went on a trip to Newcastle for a few days last week, too bad i didnt read this first
Title: Re: oscillation on idle after throttle close
Post by: Seight-v8 on September 30, 2013, 08:07:54 PM
just my luck.....if your ever passing again let me know....i'm about 45mins from Newcastle.....

cheers

scott