g60-r 0 Posted April 3, 2007 hi all, spent my first day tweeking my 1990 1.9 scince buying her last week. decided to treat her to some new HT leads, plugs (ngk from gsf) dizzy cap, rotor arm and air filer. while i was at this area i also thought i'd stop a little water leek and some oil seepage from dehind the dizzy. now the prob is......... i forgot to mark the dizzy position and now can't get her running right. my idle has always been a little high (1500) and i discovered this can be lowered by rotating the dizzy anti-clockwise. so set the idle to 1000 and all seemed cool. not so though, she is down on power especially at the higher end of the rev range. how can i set the timing up correctly and keep the idle low???? also, rotating the dizzy anti-clockwise, has this advanced or retarded the timing? cheers P.S the new plugs have a smaller gap than the ones in there already Share this post Link to post Share on other sites
Miles 331 1 Cars Posted April 3, 2007 It's a case of balance really, the idle can be set by the screw in the throttle body and the mixture on the AFM, The Dizy sit's in the middle of it's adjustment for a base setting then you can adjust from there every time you go out a minor tweak can be made, Share this post Link to post Share on other sites
g60-r 0 Posted April 4, 2007 i found some handy timing info in the search in the end, was typing in the wrong words so........ spent a couple of hours after work today doing loads of test runs and getting it all sorted. i recon i've got the timing pretty good now, don't think it's pinking, idling just under 1000 ,new hose from TB to vac advance unit, new plugs, leads, ect. She is running nicely and pulling strong...........................but on a couple of the test runs, both at quite different timing setting i hit a flat spot somewhere between 4000-5000 rpm. happened twice but both times when accelerating in 3rd from 2500 rpm up hill on full throttle. as i said, happened twice out of about 10-12 runs on same peice of road. running v-power in the tank. any ideas??? have i got the timing wrong or is it something else cheers all Roo Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted April 4, 2007 (edited) The flat spot sounds like a loose/bad connection. make sure all the HT leads are cliped on fully on both the plugs and cap. To set up the mixture and dizzy I bought a Gunson gas analyser for £35 off ebay (second hand ones are usually as good as new) When I checked the timing with the book figure using a strobe the car ran flat with no power. I kept advancing it adjusting idle the mixture to suit till the power came back. You can keep advancing it till the power drops off again, mark that point as too much advance. The timing changes though with the fuel you use, so I try to find a compromise and carry an 11mm spanner around with me everywhere I go (only with a 205 eh!) Edited April 4, 2007 by ALEX Share this post Link to post Share on other sites
Andrwn8304 0 Posted April 5, 2007 The flat spot sounds like a loose/bad connection.make sure all the HT leads are cliped on fully on both the plugs and cap. To set up the mixture and dizzy I bought a Gunson gas analyser for £35 off ebay (second hand ones are usually as good as new) When I checked the timing with the book figure using a strobe the car ran flat with no power. I kept advancing it adjusting idle the mixture to suit till the power came back. You can keep advancing it till the power drops off again, mark that point as too much advance. The timing changes though with the fuel you use, so I try to find a compromise and carry an 11mm spanner around with me everywhere I go (only with a 205 eh!) Which timing mark on the strobe did you set it too? As theres 2 marks the 1 towards the front of the car is TDC set it towards the rear its a bit fiddly to see the mark with the filler pipe and other cables being in the way. Share this post Link to post Share on other sites
jonah 1 Posted April 5, 2007 She is running nicely and pulling strong...........................but on a couple of the test runs, both at quite different timing setting i hit a flat spot somewhere between 4000-5000 rpm. happened twice but both times when accelerating in 3rd from 2500 rpm up hill on full throttle. as i said, happened twice out of about 10-12 runs on same peice of road. running v-power in the tank. any ideas??? have i got the timing wrong or is it something else Incorrect timing won't cause a flat spot, it'll either cause pinking if too advanced, or (as you've found out) a lack of power if too retarded. There is a mention in the Haynes manual about incorrect routing of the coil HT lead causing misfires. Since you've just replaced this it could be a possibility. I think what happens is that the cable from underneath the dizzy to the ignition amp picks up interference from the HT lead, which confuses the ignition amp. You could try rerouting these cables making sure they're not too close together, and if they have to cross over then do it at right angles and don't run them parallel. Share this post Link to post Share on other sites
g60-r 0 Posted April 5, 2007 sounds like good theory, i'll give it a go and up date on the result. had a good drive in her today though, no flat spots and going really strong Share this post Link to post Share on other sites