Hi there.
I am not a mechanic by any means so please forgive my less than technical detail and please also forgive me if I say something that just sounds silly as I am also interpreting discussions I have had with my mechanic in the past and may have misunderstood him also.
A bit of history just to describe what I have done with my X1/9 since I purchased it.
I have owned my 1500 X19 for over 18 months. It has two Weber DCNF 40's.
Initially my mechanic and I were really struggling with trying to get the weber's tuned and balanced etc. He reported to me that he discovered that the two carb's throttles were linked incorrectly somehow and he resolved it by reconnecting properly. I don't know about this all I know is that I drove the car 900km interstate to drive it home when I purchased it and it seemed to go OK. It might be that the way they were connected was masking problems. He also discovered mis matched idle jets screws between the carbies. Making hard to balance idle settings?
After lots of time and not much satisfaction and a really crappy long distance road trip that I shoould noot of finiished but turned for home, I ended up paying the $$$ and had both of the carbs fully reconditioned or kitted. Not cheap!
Once back on the car I could tell the difference (as one should). The response was much smoother throught the rev range. Idle was better also.
However, now there was a niggling hesitation as the RPM went through about 5,500 revs.
It was hard to describe to my mechanic exactly when this would occur as it appeared to me to be intermittent or at least variable. My mechanic would ask me about whether it occured whilst under load or not etc. Remembering back it seemed to be more noticable at least in gears 2,3 and 4 not 1st or 5th so much but hey it's hard to replicate lab conditions out on the road. That's all I could say at the time.
I did find it hard for to keep track of all the things going on at one time and then to try to compare situations between a cold or hot engine, under load or not under load, top gear low gearetc. Not being a mechanic I just didn't know what was irrelevant and what was important to monitor whilst driving.
A lot of the time I know I have not been that useful to my mechanic at all.
Anyway last service he replaced the distributor's points and rectifier? or is it the capacitor? Anyway as he did this he decided to remove the distributor and he said he tightened up the advance mech springs. From this I believe he was suggesting to me that something was a little loose inside to do with the springs? and associated with the bob weight and just tightened them.
Anyway ... whether it was the points, rectifier (or capacitor) or the mechanical advance springs being tightened up the hesitation around 5,500rpm was gone.
Now onto the final problem (I hope) and the reason for this thread ...
I didn't notice it at first but I went on a long trip over a weekend and on the return trip The car suddenly decided that it was going to die. I was going up a steep incline on a mountain pass and going through a tight left hairpin turn. I was in 2nd but went to 1st gear and was revving to try to get some power back and after a few momentts later was going again.
This was the first time it happened and it has been happening every know and then since.
After driving last weekend for about a half hour I have pretty much narrowed it down to LEFT turns only. This is why I guess I keep thinking it was intermittent. Some roads turn right
I can detect *just* a small indication it might be happening even if I have little or no throttle as I coast around a left corner but of course the main problem is when I have open throttle and the car makes this large spluttering sound that sounds like it's starved of fuel starvation to me at least.
I have read through the thread by HAVEMANN here https://www.fiatforum.com/x1-9/95995-throttle-problem-cornering.html?
I have considered the idea of G forces moving my spark leads and electrical faults etc. (as per mentioned in HAVEMANN's thread)
But this is what I think from my latest driving tests:
The car has no detectable problem when I am accelerating in a straight line. The symptoms don't appear when I am under high G right turn. They only present or start rather when going through a high G left turn.
Now During the experimentation I went through on the weekend the left turns with my foot to the floor, the car would barely accelerate and was showing huge response problem like it was starving of fuel.
Know this is important I think, EVEN AFTER straightening up after the turn as long as I kept my foot down it would not recover until I either changed up a gear or simply lifted the throttle momentarily and then reapplied throttle again. It's because of this that I discount the electrical lead issue. If it is leads moving and shorting then surely the situation would improve after I straightened after the turn not be prolonged until after I lifted the throttle. My thinking is that the lift off the throttle atakes off the load and allows the fuel bowl to recover?
Now I don't know the internals of the carbs but I am thinking that the floats or the fuel in the bowls? might be more susceptible to left than right turns? Just due to physical design of the carbies?
Is there anything wrong with this logic am I missing something?
The question is ... if I am right and it is the carby float level and indeed a fuel starvation problem of sorts, what the hell is actually wrong with the carby setups? And what can I do to fix it.
I was tempted to install an electric fuel pump quite a while ago as my mechanic a long time ago suggested that the twin carbs might be using more fuel than the standard mechaniical pump can supply. Buut I think that discussion was in contect of the 5,500 rpm hesitation issue ... now solved.
In HAVEMANN's thread I think he tried and removed his also. Also I don't know how electrical pumps work as to know what improvement to expect from introducing one to the system in relation to my problem. As I said before I don't have a problem in a straight line. The Mechanical pump seems fine supplying the carbies with throttle fully open without any hesitation in that situation.
I have also tried to keep in mind that heat from the exhaust manifold could be causing a problem or making it worse but I am excluding it from the equation at the moment. The two carbies are mounted with what looks like a black rubber like gasket at the bottom of the carby base and a sheet metal heat guard has been fashioned and installed below the carbies also to replace the original heat shield used on orignal single carby. So maybe the carbies are protected reasonably from heat.
The orginal blower still runs via a manual switch in the cabin but there is no hose to direct air over the twin carbs and of course the original plastic carby shroud is gone to. If heat is a problem I could always make a new shroud out of sheet metal and attach a hose from it to the blower and have air over the twin carbs in the future if necessary.
Sorry if I have raved on a bit. Lots to describe but no real understanding of cars in detail only in general as I said. I hope the above makes sense and you can see through what I am trying to describe as I would really love to hear from someone that can put a finger on the likely cause and maybe suggest a fix.
Regards
Keith
I am not a mechanic by any means so please forgive my less than technical detail and please also forgive me if I say something that just sounds silly as I am also interpreting discussions I have had with my mechanic in the past and may have misunderstood him also.
A bit of history just to describe what I have done with my X1/9 since I purchased it.
I have owned my 1500 X19 for over 18 months. It has two Weber DCNF 40's.
Initially my mechanic and I were really struggling with trying to get the weber's tuned and balanced etc. He reported to me that he discovered that the two carb's throttles were linked incorrectly somehow and he resolved it by reconnecting properly. I don't know about this all I know is that I drove the car 900km interstate to drive it home when I purchased it and it seemed to go OK. It might be that the way they were connected was masking problems. He also discovered mis matched idle jets screws between the carbies. Making hard to balance idle settings?
After lots of time and not much satisfaction and a really crappy long distance road trip that I shoould noot of finiished but turned for home, I ended up paying the $$$ and had both of the carbs fully reconditioned or kitted. Not cheap!
Once back on the car I could tell the difference (as one should). The response was much smoother throught the rev range. Idle was better also.
However, now there was a niggling hesitation as the RPM went through about 5,500 revs.
It was hard to describe to my mechanic exactly when this would occur as it appeared to me to be intermittent or at least variable. My mechanic would ask me about whether it occured whilst under load or not etc. Remembering back it seemed to be more noticable at least in gears 2,3 and 4 not 1st or 5th so much but hey it's hard to replicate lab conditions out on the road. That's all I could say at the time.
I did find it hard for to keep track of all the things going on at one time and then to try to compare situations between a cold or hot engine, under load or not under load, top gear low gearetc. Not being a mechanic I just didn't know what was irrelevant and what was important to monitor whilst driving.
A lot of the time I know I have not been that useful to my mechanic at all.
Anyway last service he replaced the distributor's points and rectifier? or is it the capacitor? Anyway as he did this he decided to remove the distributor and he said he tightened up the advance mech springs. From this I believe he was suggesting to me that something was a little loose inside to do with the springs? and associated with the bob weight and just tightened them.
Anyway ... whether it was the points, rectifier (or capacitor) or the mechanical advance springs being tightened up the hesitation around 5,500rpm was gone.
Now onto the final problem (I hope) and the reason for this thread ...
I didn't notice it at first but I went on a long trip over a weekend and on the return trip The car suddenly decided that it was going to die. I was going up a steep incline on a mountain pass and going through a tight left hairpin turn. I was in 2nd but went to 1st gear and was revving to try to get some power back and after a few momentts later was going again.
This was the first time it happened and it has been happening every know and then since.
After driving last weekend for about a half hour I have pretty much narrowed it down to LEFT turns only. This is why I guess I keep thinking it was intermittent. Some roads turn right
I can detect *just* a small indication it might be happening even if I have little or no throttle as I coast around a left corner but of course the main problem is when I have open throttle and the car makes this large spluttering sound that sounds like it's starved of fuel starvation to me at least.
I have read through the thread by HAVEMANN here https://www.fiatforum.com/x1-9/95995-throttle-problem-cornering.html?
I have considered the idea of G forces moving my spark leads and electrical faults etc. (as per mentioned in HAVEMANN's thread)
But this is what I think from my latest driving tests:
The car has no detectable problem when I am accelerating in a straight line. The symptoms don't appear when I am under high G right turn. They only present or start rather when going through a high G left turn.
Now During the experimentation I went through on the weekend the left turns with my foot to the floor, the car would barely accelerate and was showing huge response problem like it was starving of fuel.
Know this is important I think, EVEN AFTER straightening up after the turn as long as I kept my foot down it would not recover until I either changed up a gear or simply lifted the throttle momentarily and then reapplied throttle again. It's because of this that I discount the electrical lead issue. If it is leads moving and shorting then surely the situation would improve after I straightened after the turn not be prolonged until after I lifted the throttle. My thinking is that the lift off the throttle atakes off the load and allows the fuel bowl to recover?
Now I don't know the internals of the carbs but I am thinking that the floats or the fuel in the bowls? might be more susceptible to left than right turns? Just due to physical design of the carbies?
Is there anything wrong with this logic am I missing something?
The question is ... if I am right and it is the carby float level and indeed a fuel starvation problem of sorts, what the hell is actually wrong with the carby setups? And what can I do to fix it.
I was tempted to install an electric fuel pump quite a while ago as my mechanic a long time ago suggested that the twin carbs might be using more fuel than the standard mechaniical pump can supply. Buut I think that discussion was in contect of the 5,500 rpm hesitation issue ... now solved.
In HAVEMANN's thread I think he tried and removed his also. Also I don't know how electrical pumps work as to know what improvement to expect from introducing one to the system in relation to my problem. As I said before I don't have a problem in a straight line. The Mechanical pump seems fine supplying the carbies with throttle fully open without any hesitation in that situation.
I have also tried to keep in mind that heat from the exhaust manifold could be causing a problem or making it worse but I am excluding it from the equation at the moment. The two carbies are mounted with what looks like a black rubber like gasket at the bottom of the carby base and a sheet metal heat guard has been fashioned and installed below the carbies also to replace the original heat shield used on orignal single carby. So maybe the carbies are protected reasonably from heat.
The orginal blower still runs via a manual switch in the cabin but there is no hose to direct air over the twin carbs and of course the original plastic carby shroud is gone to. If heat is a problem I could always make a new shroud out of sheet metal and attach a hose from it to the blower and have air over the twin carbs in the future if necessary.
Sorry if I have raved on a bit. Lots to describe but no real understanding of cars in detail only in general as I said. I hope the above makes sense and you can see through what I am trying to describe as I would really love to hear from someone that can put a finger on the likely cause and maybe suggest a fix.
Regards
Keith
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