paulleo 72 Posted October 16, 2002 Share Posted October 16, 2002 hi all, can anyone help i have g.e.m.s management system controlling the weber 45's on my zetec it is coloured blue is it ignition only or fully mappable? Quote Link to comment Share on other sites More sharing options...
stu999 Posted October 17, 2002 Share Posted October 17, 2002 The question is a bit confusing but if I understand correctly, if you have Webers fitted, unless they have been modified into throttle bodies (do you have injectors fitted) then it will be ignition only. But the ECU will still probably be mappable for ignition timing. Some systems have a throttle position sensor fitted to the carbs to take into account the throttle position in relation to engine speed. This doesnt have any relevance to the carb/mixture requirements though. The carbs work independantly, and need to be rejetted to change fuelling. HTH Stu. Quote Link to comment Share on other sites More sharing options...
Kevin Wood Posted October 17, 2002 Share Posted October 17, 2002 Hi There, I have the same unit. I think it's a minidls2, which only does ignition. There are units further up the range which do injection as well. Don't know if you can get a trade in. www.gems.co.uk is their web site, I think. A little info there. I think Omex have recently taken over this business though. It is mapped, with speed sites from 800 rpm to about double what a Zetec will rev to in 400 RPM steps. It has a 3D map, with load sites normally controlled by a throttle pot or baro sensor and will also make corrections for intake temperature and baro pressure. with appropriate sensors. It has a programmable rev limiter and an output that can be configured as a shift light or tachometer drive. What are you wanting to do with it? I could probably borrow the mapping software if you want to program it. Kevin Quote Link to comment Share on other sites More sharing options...
paulleo 72 Posted October 17, 2002 Author Share Posted October 17, 2002 at present the car runs very rough at low rpm once you get to about 3500 rpm it goes like stink the problem is its not very good for road driving can it be remapped to run better at lower rpm or do the carbs just need balancing the fuel consumption is terrible about 85 miles to £30 worth of juice. Quote Link to comment Share on other sites More sharing options...
steppenwolf Posted October 17, 2002 Share Posted October 17, 2002 This sounds very much like a carb. problem to me. I think that the ECU for the ignition aspect is not the underlining cause of the rough running. A trip to a rolling road would be the best start to have the carburettors adjusted before you start looking at the mapping of the ECU which will effect ignition only in this configuration. There may, however, be an input to the ignition ECU from the carb. in the form of a TPS (throttle position sensor) which tells the ECU how far open the throttle is. It is not uncommon for an engine to appear to be running 'well' at higher revs. but to run like a dog at low revs. - the sheer inertia of the thing masking the fact that it is running poorly. It does sound somewhat rich doesn't it? Quote Link to comment Share on other sites More sharing options...
Blatman Posted October 17, 2002 Share Posted October 17, 2002 Sounds like a carb/fuelling problem to me. It's rare for maps to develop faults, but it is more common to have trouble with one of the input sensors, or something else, externally, to change, causing the problem. As with most things like this, my preferred MO is to start with some basic checks. New plugs, and air filter(s) wouldn't go amiss (unless they're less than 12 months/6000 miles old). Check the screws holding on the carb venturis (underneath each choke on the outside of the carb. Item 28 on this diagram, which holds in item 17.), as they can work loose, and will cause all sorts of problems. Oooh, me an' Stepps are cross posting. I'll stop here then, 'cos you've got enough to be getting on with for now.... Quote Link to comment Share on other sites More sharing options...
paulleo 72 Posted October 18, 2002 Author Share Posted October 18, 2002 thanks i'll have a go this weekend, should i be getting better mpg ? or is this about right seems a little excessive after speaking two other westie owners. Quote Link to comment Share on other sites More sharing options...
Blatman Posted October 18, 2002 Share Posted October 18, 2002 85 miles on 30 quids worth of gas? Oh yes, you should be getting much better than that........... If you were getting better mileage "before", and it's got worse recently, then something has changed (it's VERY doubtful it'll be anything internal to the ECU). You *just* need to do a few checks.............. Quote Link to comment Share on other sites More sharing options...
paulleo 72 Posted October 18, 2002 Author Share Posted October 18, 2002 I haven't had the car that long it has allways run a little rough and the fuelling has been bad since i got it what should i be getting under normal driving conditions. Quote Link to comment Share on other sites More sharing options...
Blatman Posted October 18, 2002 Share Posted October 18, 2002 Difficult to say, but with a set of 45's properly set up, and not spending the whole time at full throttle, I'd expect to see anything from 120-150 miles to a full tank of fuel. The next question then is, are you filling up with a full £30 when the tank is empty (I'm guessing yes, 'cos I've never got 30 quids worth of fuel into either of my Westfields), or when the gauge says empty? If you're relying on the gauge alone, and it's reading empty after 85 miles from filling up, then the guage may well be telling you lies. However, £30 is a lot of fuel for a Westfield tank, so I'm guessing it's actually empty when you fill it. So you have a problem. Do the checks me an' Steppenwolff have outlined, and try a new set of plugs and air filters (or clean the ones you have, if they're cleanable....), and if there is nothing obvious that's loose or failing (coil/leads, plus carb venturi screw, etc etc), including checking for air leaks around the carb/inlet manifold interface (do this by letting the car idle, then spraying a fine mist of WD40 around the area of the carb/manifold junction. If the revs rise whilst spraying, you have an air leak..........). Once you'ce checked all that, and rectified any obvious faults, then a trip to the rollers is definitely the next step. Quote Link to comment Share on other sites More sharing options...
Kevin Wood Posted October 20, 2002 Share Posted October 20, 2002 My Zetec probably does 25 - 30 MPG on 45's. This means a comfortable 120 miles on a standard tank but I've never put anything like 30 quid's worth in in one go. I'd probably expect about 200 miles on that amount of fuel. DO you have a long range tank perhaps? Sounds like you need to get it checked out ASAP because that level of fuel consumption is going to lead to oil contamination and bore wash, not to mention a larger hole in the wallet than a rolling road tune would inflict. Make sure the basics have been checked before you go to a RR as this will save you money. Kevin Quote Link to comment Share on other sites More sharing options...
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