running smooth on dyno, rough on road

discopigg · Post by **discopigg** » Mon May 09, 2011 2:13 pm

Hey all, just looking for some help troubleshooting.
My ET started misbehaving recently and i thought it was in connection to someone playing with the microtech handheld.
I wanted to properly tuned anyway and took it to maztech to get the microtech mapped and tuned nicely.
When it was on the dyno it was running nicely through the range and gave pretty smooth curves on the readout. As soon as it was down and on the road though it all went wrong again. At a guess it sounds like it's occasionally not firing on one of the cylinders(when the foot is down hard i get the occasional big back fire) and generally runs a little rough. I'm getting sparking from all the leads and the spark plugs were recently replaced.
I've been thinking dizzy might be the issue(just bought a replacement one but haven't fitted it yet) but i can't for the life of me think why it would be fine on the dyno but nasty on the road?
I'm an amateur when it comes to mechanics so it's quite possible i'm missing something obvious, so any suggestions are welcome

Callumgw · Post by **Callumgw** » Mon May 09, 2011 2:21 pm

What do you mean by:

discopigg wrote:I'm getting sparking from all the leads

C

Post by **shanec86** » Mon May 09, 2011 6:09 pm

take it back to maztech?

discopigg · Post by **discopigg** » Tue May 10, 2011 1:08 pm

Callumgw
Posted: Mon May 09, 2011 2:21 pm Post subject: Re: running smooth on dyno, rough on road
What do you mean by:

discopigg wrote:
I'm getting sparking from all the leads

C

Sorry that's really poorly phrased. Just meant that the coil pack seems to be working fine and the line to the distro will spark when I give it somewhere to earth to.
As for taking it back to maztech, I probably will later but I'm a student and as such pretty broke and their time isn't cheap so any trouble shooting I can do myself is always good.

Kimmo · Post by **Kimmo** » Tue May 10, 2011 5:20 pm

Quote button's at the top right of posts, dude.

discopigg · Post by **discopigg** » Tue May 10, 2011 6:19 pm

Kimmo wrote:Quote button's at the top right of posts, dude.

Yup, was just doing it on my iphone and couldn't for the life of my fat fingers press the tiny thing..

Post by **shanec86** » Tue May 10, 2011 9:24 pm

its hard to say without knowing the car/ seeing what chasers have done. but if you payed for dyno time to tune it and it runs like crap on the road, it wasnt done properly