Last ride gave some problem. Both cold and warm starts are problem-free. Stumbling mainly occurs in 2nd gear at +/- 2000 rpm and when giving full throttle. Higher revs pose no problem, even accelerating full throttle above 3000 revs poses no problem. My first idea was to add some kind of injector cleaner. Gave slight improvement. Tank was 1/2 full so I filled it up with 98 ron. Again slight improvement at least after +/- 10 km. On Sunday I have a fairly long distance to ride +/- 2 x 150 km. What do you think......to venture or check something else first. All suggestions are welcome
Check your plug leads & lead extenders for electrical resistance, plugs for not being fouled and distributor cap / carbon brush for signs of damage/oil ingress. When you put it back together make sure the lead-extender and extender -plug are properly pushed into place.
This. Its much more likely to be ignition related than fuel system. Check plug leads for continuity - they will still work for a while even if broken inside but will get progressively worse. Chek the extenders for signs of burn-through / arcing. Could also be just bad gas - when did you last fill it?
Thanks guys. It won't be a problem with petrol, it was half full and filled yesterday, it gave an improvement and I only drove 10 km, maybe it will disappear after a few more km. Afterwards I will check all the electrical components mentioned. No spare time for the moment. I l keep yo posted.
As reported on Sunday, +/-150 km trip and the same back. First +/- 30 km still a small problem. Afterwards no more problems. One could conclude that it is a cold engine problem, but that was not the case as before starting the return journey, the car stood still for 5 hours and no problem at all on the return journey. My conclusion but correct me if I am wrong, dirty injectors or condensation in gasoline? Notwithstanding that, I will soon be checking all the indicated electrical parts as sinds i have the car (+/-1 and1/2 year) that is not been done
Hi all, I am new here, just bought my first Ferrari a few weeks ago (1988 328 gts, French delivered). I am very happy with the car and have driven it a lot since I have got it. Lately, I seem to meet a similar problem to Zenobie's, it started misfiring, mostly when the oil was hot (above 90C), mostly at low rpm. I have inspected all the plug extensions and found one that was missing a piece, which oddly was not found, I therefore replaced it. The others showed slight burn marks but no holes. It is now worse than before, but intermittently works better at moments. I am taking it this week to a specialised mechanic that takes care of several 328, I will hopefully get back here with the solution (to my problem at least). In any case, happy to be part of the community.
The car came back from the shop, so far it seems fine although it didn’t get up to great oil temperature on the way back. It turns out that I had missed one of the plug extensions that was burnt through, and some wires did not have a good lock on the extensions. One distributor cap was also burnt. The spark plugs themselves all look pretty much the same which should indicate injection is working correctly.
Was tired of having to add injector cleaner every time I drove and since I can't find anything in the car history about injectors, I decided to replace all injectors. Afterwards I checked for fuel loss and that is not the case. The test drive was anything but positive.......no improvement, the situation is the same as when I started the thread. According to the history, the spark plug cables, extenders and spark plugs were replaced 2 years ago. Any suggestions?
I would pull the caps and see if there’s any oil setting in them. Not uncommon to have a seeping O- ring that will cause issues like this.
. According to the history, the spark plug cables, extenders and spark plugs were replaced 2 years ago. Any suggestions? [/QUOTE]Before you dive too deep I would check the resistance of the leads and extenders from the terminals in the distributor caps to the spark plugs, get a CIS test kit and check fuel pressures and residual pressure leak down time. If all this checks out take it to someone with professional CO and HC measuring equipment to check these values. If you don't know where the spark plugs came from, also change them and ensure you purchase from a vendor who sells genuine components. There is a lot of fake NGK plugs in the market. if oil is leaking into the distributor caps you will see this when the spark plug leads are checked.
I am doing first but these on the interior side are very difficult even with the hood removed there is too little space to work with a standard extension. Once I found a reasonable key and extension ( extension has to be shorter than the standard on )I dropped the whole thing, so it is now on the floor pan and there is no way to just pick it up. Will probably have to take the wheel off and remove it because where the car is now there are no engine supports available so taking the floor pan off is not an option Did it.....S..T did help no italian hands could reach such far but there is a small place between the buttomplate and the exhaust so get the tool out. Plugs are out to and they al look the same Champion A6GC and all with the same kind of verry litle carbon deposite. But while cleaning I noticed that the imprint reference on the plugs at the back .... the most difficult to get out the color and the place of ref imprint were on a slightly higher place........ took a closer look and there is also something stamped on the metal part....... you guessed it, the front and back are different. The last maintenance was carried out on behalf of the previous owner and the invoice stated 8 spark plugs.... hm, it could be a coincidence but it could be that the rear ones had not been replaced. Anyway, is Champion A6GC the the correct type ? I searched a bit further and removed the rubber cover from over one of the distributors....... is the small hole normal, I don't think so. I would like some advice because I can't look at the inside for the time being, I want to mark the plug cables first before I remove them, they have to be removed otherwise you can't get to the bottom screw of the distributor
Those are Gold Palladium plugs and the correct grade. Very odd that the lettering is not consistent. I would be leaning towards thinking Fake. But i am a skeptic,having been caught out with NGK fakes. Thankfully, not on an eight cylinder engine. The aperture in the cap is normal. This is intended as a breather, i think. You ought to remove both caps and measure the lead resistance from the distributor lead posts to the end of the extenders. Also check that the carbon brushes are ok and there is no oil leakage into the caps. Be careful when removing the caps.It is easy to break off the carbon brushes.
The original Cavis 400 leads would have been 0.5 k ohm-1 k ohm. Modern resistive replacements are more like 3 k ohm - 5 k ohm. In both cases the longer the lead, the greater resistance.
Will do the dark test to, did this in the past on many cars, amazing what you see when the leads are bad. Must be age (73) that i did not think about that
I would first look at the ignition modules mounted on top of the coils. When they go, they go smoothly so its not an on/off. Intermittent bad running is always a hard to find issue but these modules ( look for cross reference, you buy the Bosch replacement for less than $50) are in quite a few similar situations the problem.
possibly yes, but i do not have a real clue there. but if you still have the old original ones, from Magneti Marelli, i would not give it a second thought, if they are not broken now they will be at some point in time relatively soon. I think the Bosch replacement is mentioned somewhere in the cross-reference section. Or somebody around here will know and chime in.
Possibly found the error. Started with measuring resistance plugs = all the same value Test extenders, 7 look internally and externally as new, no traces of sparking, 1 hmmm corrosion on the contact inside. When measuring the corroded one I do get +/- the same resistance value, but I have to keep grinding with the measuring pin, otherwise no measurement. Spark plug inserted and no measurement without wiggling the spark plug. It also has a kind of powdery substance inside (minimal) that could be released due to poor connection (spark breakdown?) of spark plug and extender. None of the other extenders have this. Could that be the problem? Anyone as a good lead as where to get them in Europe?
Try cleaning the corrosion with a Dremel tool and small wire brush attachment, or small grinder attachment. Then blow out thoroughly with compressed air. Reinsert, perhaps with a small dab of dielectric grease, and see if the car runs well without the stumble. If it does, you've found your problem. The extenders can indeed cause poor running if they fail. I had a similar running problem with my '76 Euro GTB, and it turned out to be a bad extender. In my case, there was a crack in the extender with evidence of arcing. I sourced new extenders from Superformance UK.
Found some more oddities. Distributor cap of the front cylinder bank internally, a little corrosion on the 4 connection points. Distributor cap rear cylinder bank also no significant corrosion, however the carbon pin was completely pressed in and stuck.I know this can't be the problem because if the pin wasn't transmitting any current the entire front cylinder bank would be completely dead. But it certainly won't do any good to the whole thing WD40 and tweezers had to be used to make the carbon pin free and springy. Still no test drive as the spark plugs only arrive today @ Anthony, Dremel treatment in the extenders is risky because the spring that holds the spark plug top is really very thin. I try if contact spray is a temporary solution. New extenders will be ordered
As all ready posted in my other topic but more appliable to this one What now is in the car is Bosch new brass injectors and yes the result was not better than before with the old type bosch. Why the result was dissapointing?......because now i know that what was not the cause! As i reported last week i found out 1. that the front and the back sparks are not the same (replaced theme all but do not think that was the problem) 2. one of the extenders was oxidite, cleaned it with contact spray but will be replaced next week when i have the new ones delivered 3. In one of the distributors the central stift was blocked and dit not move at all, make it moveble with a lidle bit of WD40 4. Eh My, i think an eventual cooling problem................had nothing to do whit the problem, as Brian said the thermostat and the radiator plug do what they have did all the time I am grateful to EVERYONE who did the effort to try to help The1.2.3 things where 2 hours a go rectified and after a test drive ............... The car runs like never before. What was the cause now? I think the extension and the stuck central carbon pin in the distributor. My "cooling problem" was actually not a problem, as well as my idea that it was condensation in petrol and deposits on injectors were therefore wrong assumptions. Now just have the CO regulated I hope everybody is happy, anyway i ame for 100 % Great forum, somethimes animated always helpfull
