this morning i got into my new v.s. and noticed that the tach was reading about 500-700rpm high and jumping all over the place. nothing different about today other than it is raining. anyone have any ideas?
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this morning i got into my new v.s. and noticed that the tach was reading about 500-700rpm high and jumping all over the place. nothing different about today other than it is raining. anyone have any ideas?
George:
Sounds like a loose or corroded electrical connection. Get under the dash and wiggle the connections on the back of the tach, or, better yet if you can see up in there, grasp the body of the little terminal tabs on the back of the Tach and pull them off and then put them back on again (once or twice each - do them one at a time to make sure they go back where they were).
Notice the color of the wires going to the back of the tach. There should be a similar color wire going to the "-" side of the ignition coil in the engine compartment - that's the signal wire driving the tach. Depending on what you have for terminals on your coil (either push-on tabs or ring-terminals and nuts) either pull them off and then push back on a few times (to clean the connection) or remove the nut and ring-terminals, clean the ring terminals with sandpaper or steel wool and replace everything. That should clean things up such that if it is a dirty or intermittant contact it should cure it.
Let us know what happens after this.
gn
Sounds like a loose or corroded electrical connection. Get under the dash and wiggle the connections on the back of the tach, or, better yet if you can see up in there, grasp the body of the little terminal tabs on the back of the Tach and pull them off and then put them back on again (once or twice each - do them one at a time to make sure they go back where they were).
Notice the color of the wires going to the back of the tach. There should be a similar color wire going to the "-" side of the ignition coil in the engine compartment - that's the signal wire driving the tach. Depending on what you have for terminals on your coil (either push-on tabs or ring-terminals and nuts) either pull them off and then push back on a few times (to clean the connection) or remove the nut and ring-terminals, clean the ring terminals with sandpaper or steel wool and replace everything. That should clean things up such that if it is a dirty or intermittant contact it should cure it.
Let us know what happens after this.
gn
i'll check it out this afternoon. sounds like it may be a humidity/ poor connection issue. i'll let you know how i make out...
i checked all of the terminals; wiggled them around, etc. they looked clean and new. the tach is still jumping around. any other thoughts?
Make sure the ground to the Tach is clean and secure, too (all the way back to the hard ground point).
If that doesn't do it, then it's probably time to contact Kirk for a new replacement tach.
If that doesn't do it, then it's probably time to contact Kirk for a new replacement tach.
My tach guage came with a 1/2" dia X 1" diameter line filter thing-a-ma-bob that you wire between the coil and tach. The third wire then goes to a good ground.
FYI,
Jerome
FYI,
Jerome
George,
Your still under warranty, call Vintage. Kirk has probably seen this before.
-=theron
Your still under warranty, call Vintage. Kirk has probably seen this before.
-=theron
George; I just rode my car today and have the exact same problem; 500-700 rpm's higher and kind of jumpy (not all over the place, though). My car is a 2004 VS too; maybe Kirk got a defective batch because the original tach that was installed in the car wasn't working when I got the car delivered here. After some tests here and there, Kirk sent another unit which I installed. It was working perfectly until today....wonder what it is. I'm suspecting those units are not Brazilian VDO; the package had another brand name on it and it said Made in China.
Richard,
Kirk at VS sent the Brazilian VDO Tach and gauges to a Chinese manufacterer, and asked him to replicate, the replicas. Kirk and John at JPS went in together on a lrge quantity of these chinese instruments, and at this point those are the gauges that have benn sold and installed for about a year by Kirk. I know because Kirk told me the story about 6 months ago.
Gclarke "The vacaville Guy"
Kirk at VS sent the Brazilian VDO Tach and gauges to a Chinese manufacterer, and asked him to replicate, the replicas. Kirk and John at JPS went in together on a lrge quantity of these chinese instruments, and at this point those are the gauges that have benn sold and installed for about a year by Kirk. I know because Kirk told me the story about 6 months ago.
Gclarke "The vacaville Guy"
Wow, Gary! I'm amazed at how much we get to learn here! Thanks for the input Bud!
Quick Story:
I worked in Engineering at Data General (mini-computer maker) back in the 80's, when the Far East Sales Director brought in one of our Nova 3 mini-computers for us to "look at". We wondered why, but opened'er up and first, found that all of the mechanical hardware was really poor quality (for us) - like crummy screws, sheetmetal and stuff - a little surprising, like "How did this get through QA?".
Next, we found LOTS of components with different markings than the ones we used, like they came from different manufacturers. This got us really curious, so we investigated right down inside the printed circuit board but there we didn't find anything different - circuit etches were all there, and even some know etch errors were there, along with microscopic etches of the designers' initials.
Then one of the guys in the lab told us he found the board laminate material was different - not what we used and actually poorer quality.
When we went to the guy who brought it to us he said he bought it in Mainland China - it was an imperfect knock-off of our Nova 3, and he said they had made THOUSANDS of them! They had even managed to duplicate a 6-layer mother board, and the only way we knew to do this was to successively shave the board to expose each layer to duplicate it! All this, and never paid a royalty......
I worked in Engineering at Data General (mini-computer maker) back in the 80's, when the Far East Sales Director brought in one of our Nova 3 mini-computers for us to "look at". We wondered why, but opened'er up and first, found that all of the mechanical hardware was really poor quality (for us) - like crummy screws, sheetmetal and stuff - a little surprising, like "How did this get through QA?".
Next, we found LOTS of components with different markings than the ones we used, like they came from different manufacturers. This got us really curious, so we investigated right down inside the printed circuit board but there we didn't find anything different - circuit etches were all there, and even some know etch errors were there, along with microscopic etches of the designers' initials.
Then one of the guys in the lab told us he found the board laminate material was different - not what we used and actually poorer quality.
When we went to the guy who brought it to us he said he bought it in Mainland China - it was an imperfect knock-off of our Nova 3, and he said they had made THOUSANDS of them! They had even managed to duplicate a 6-layer mother board, and the only way we knew to do this was to successively shave the board to expose each layer to duplicate it! All this, and never paid a royalty......
Ricardo
That sounds like a loose ground connection somewhere.
Check and recheck the grounds by having someone watch the tach as you wiggle all associated wires as well as the surrounding and main ground comnnections.
Alan M
That sounds like a loose ground connection somewhere.
Check and recheck the grounds by having someone watch the tach as you wiggle all associated wires as well as the surrounding and main ground comnnections.
Alan M
I emailed Kirk and he replied that the gauges are actually manufactured by VDO and that he's had some off & on problems with them. Yesterday, though, I had the engine running for a while and the tach was weird at first but soon after it stabilized. I wonder what could it be....
Thanks Alan; I'll look into it further....I hope you're right; it's kind of a hassle to be replacing the tach every couple of months....
i've checked every wire on mine and there is no improvement. i contacted kirk and he is mailing me a new one. he claims that although the guages look good, they aren't the best quality. i'll let you know if this fixes the problem.
I'll second Kirk's opinion of these gauges. I bought a set from him a while back and they're OK, but that's about it. My trip odometer doesn't like to work much, so I just don't bother with it, although the tach and others seem OK. A set of gauges from a 914 or 944 might have been nice.......
I'm not sure if you know this, but the trip odometer has plastic gears. If you try to reset it while the car is moving they will break.
Eddie
Eddie
Thanks for that tip Eddie, ehew, was going to use the trip odomoter in laying out the Southern Oregon October tour. Saved me an expense as mine is off warrenty now.
Bruce
Bruce
NOW you tell me.........
Thanks, Eddie...........gn
Just curious.......other than hauling it all apart, is there any fix (probably not?)
Thanks, Eddie...........gn
Just curious.......other than hauling it all apart, is there any fix (probably not?)
As always, I'll try to investigate everything first (loose connections, et. al) before bothering Kirk for a new one. I was wondering: Is the diameter of these gauges the same as the Brazilian VDO's sold by CB Performance? It might be a good idea to change them all...I don't know....
That was my question also "What is the alternative to the Far East specials ?"
i replaced my tach...no improvements. any other ideas?
Somehow I get the feeling that these units are not very good to start with if the failure rate is so high.....
George:
If you have a voltmeter, you could pull the lead off of the tach and attach it to the "+" probe of the voltmeter, and ground the "-" voltmeter lead. Set the voltage range to 25 VDC and start the engine. You should see a rise in the voltmeter needle if everything is working on the back end. If not, try lowering the range to 10 or then 5 VDC if need be to get the needle in the bottom 1/4 of the scale when idling. If you get a meter indication, it should then rise and fall with the speed of the engine. If it doesn't move at all, then it's something on the back end of the wire to check out, since it's not sending any voltage to the tach.
If it IS sending voltage to the tach (hopefully, more then 2-3 volts), then it probably is the tach.
Also make sure that the constant +12V going to the tach from the key circuit is working, and that the tach ground is solid.
If all that fails, then email me and we can meet out in Grafton (1 hour West or where you live) and see if we can track the culprit down.
gn
If you have a voltmeter, you could pull the lead off of the tach and attach it to the "+" probe of the voltmeter, and ground the "-" voltmeter lead. Set the voltage range to 25 VDC and start the engine. You should see a rise in the voltmeter needle if everything is working on the back end. If not, try lowering the range to 10 or then 5 VDC if need be to get the needle in the bottom 1/4 of the scale when idling. If you get a meter indication, it should then rise and fall with the speed of the engine. If it doesn't move at all, then it's something on the back end of the wire to check out, since it's not sending any voltage to the tach.
If it IS sending voltage to the tach (hopefully, more then 2-3 volts), then it probably is the tach.
Also make sure that the constant +12V going to the tach from the key circuit is working, and that the tach ground is solid.
If all that fails, then email me and we can meet out in Grafton (1 hour West or where you live) and see if we can track the culprit down.
gn
i'll give it a try. offhand, it is definitely sending voltage, since the tach works. it seems as though it's a bad connection somewhere, considering that the needle literally dances around the correct rpm. i guess i should also do a continuity check to make sure that my wires didn't get chaffed or something...
George:
Check under "Events".......I'm hosting a "Rhode Island Coastal Village Tour" this weekend. If you can make it, we'll try hooking up a different tach - I have tach/dwell meter test instrument we can attach either right at the distributor or then up at the dash to see what it looks like. With that, we can decide whether it's the disti, the wires or the new/old tach(s).
I guess you're getting voltage or it wouldn't work at all......
Check under "Events".......I'm hosting a "Rhode Island Coastal Village Tour" this weekend. If you can make it, we'll try hooking up a different tach - I have tach/dwell meter test instrument we can attach either right at the distributor or then up at the dash to see what it looks like. With that, we can decide whether it's the disti, the wires or the new/old tach(s).
I guess you're getting voltage or it wouldn't work at all......
Mine does exactly the same thing...makes you wonder....
I wouldn't be surprised if there were a few out of "production run" that had similar problems - used to see things like that (a bunch of similar failures in a similar lot) often when I was in high tech, then we went after the supplier for remedy.
All I'll do to test it is to attach a dwell/tachometer test meter to the circuit and see what it acts like. If the test meter is steady, then it's the (second) tach. It the test meter jumps around, then we start looking at wiring or the distributor. It has to be something simple in the end - it's a pretty simple circuit.
Ricardo (and others) - Dwell meters were used to set distributor points before electronic ignitions. If you HAVE points, a dwell meter is THE way to set them - you can even do it while cranking the engine with the coil wire off and simply "dial them in" by watching the meter, once you get the hang of it. Another useful feature is that they can act as a tach for any number of cylinders (although you have to extrapolate for those five cylinder Audi's and V-10 Vipers - LOL!) They're usually cheap, and auto parts stores often have them - in fact, I saw one in a Sears tool department a short while ago.
A dwell meter is next to useless with electronic ignition, since there's nothing to adjust - the dwell is constant and any adjustments needed are made by the computer, but they still can be used as a test tachometer.........
gn
All I'll do to test it is to attach a dwell/tachometer test meter to the circuit and see what it acts like. If the test meter is steady, then it's the (second) tach. It the test meter jumps around, then we start looking at wiring or the distributor. It has to be something simple in the end - it's a pretty simple circuit.
Ricardo (and others) - Dwell meters were used to set distributor points before electronic ignitions. If you HAVE points, a dwell meter is THE way to set them - you can even do it while cranking the engine with the coil wire off and simply "dial them in" by watching the meter, once you get the hang of it. Another useful feature is that they can act as a tach for any number of cylinders (although you have to extrapolate for those five cylinder Audi's and V-10 Vipers - LOL!) They're usually cheap, and auto parts stores often have them - in fact, I saw one in a Sears tool department a short while ago.
A dwell meter is next to useless with electronic ignition, since there's nothing to adjust - the dwell is constant and any adjustments needed are made by the computer, but they still can be used as a test tachometer.........
gn
Thanks for the great Tip Gord! Let's see if I can find one of those....
George; did you ever get your tach working right? I got caught up doing some other things to the car and decided to leave it alone. It fixed right up after a while and now it started acting out again. I'll definitely follow the previous suggestions and check the electrical system first but somehow it seems weird since there are many coincidental malfunctioning gauges. From what I've seen, the wiring on Kirk's cars is nicely done. It has to be the instruments. The sad thing is that the Brazilian VDO's are no longer available, at least from CB Performance.
Hola, Ricardo!
If your other gauges are acting up, too, then I would suspect the ground going from somewhere under the dash to the gauges, or the +12V lead feeding the "hot" side of the gauges. Often, and especially in humid, salty climates, the connections get a bit corroded and then begin to offer resistance, and strange things happen.
Follow the +12V and ground leads back from the gauges and Check/clean the connections all along the way, including the fuse (clean BOTH the fuse AND the socket). A Dremel with a rotary wire brush attachment works very well. Just for the heck of it, you could also put some dielectric grease (it doesn't conduct) or white lithium grease on those connections to prevent corrosion in the future. I've had to do this here on the shore, too (for both RI and SC), and any in-line connections now have shrink-tubes over them with the tube ends gooped with silicon caulk. Look at your "factory" car, and you'll find the same grease on their electrical connections, too, so if it's good enough for them.......
gn
If your other gauges are acting up, too, then I would suspect the ground going from somewhere under the dash to the gauges, or the +12V lead feeding the "hot" side of the gauges. Often, and especially in humid, salty climates, the connections get a bit corroded and then begin to offer resistance, and strange things happen.
Follow the +12V and ground leads back from the gauges and Check/clean the connections all along the way, including the fuse (clean BOTH the fuse AND the socket). A Dremel with a rotary wire brush attachment works very well. Just for the heck of it, you could also put some dielectric grease (it doesn't conduct) or white lithium grease on those connections to prevent corrosion in the future. I've had to do this here on the shore, too (for both RI and SC), and any in-line connections now have shrink-tubes over them with the tube ends gooped with silicon caulk. Look at your "factory" car, and you'll find the same grease on their electrical connections, too, so if it's good enough for them.......
gn
Thanks Gord! The rest of my gauges work fine as does the rest of the car. I'll follow all your suggestions but somehow I feel the quality of these gauges, especially the tachs, is definitely inferior.
Ricardo,
What does your tach look like? Is it the one in the red car in your photo album section? Do you have the green number 356-look gauges or the black faced/white number 914 gauges, or something all together different/custom/aftermarket?
What does your tach look like? Is it the one in the red car in your photo album section? Do you have the green number 356-look gauges or the black faced/white number 914 gauges, or something all together different/custom/aftermarket?
No, TC, my car is an ivory 2004 VS. That red car in my folder was being offered to me for 10K in West Virginia but I passed; the front looks kind of crooked; maybe it was in an accident.....My gauges are the Chinese repros of the Brazilian VDO repros, whatever that means....
This is weird; weather here has been rainy for the past couple of days. I took the car out today because it was sunny. As you can see the tach had been acting up since the end of May and all of a sudden it's working fine today....there's no way to understand these Chinese engineering marvels. Could it be ground related then?
Yup.....see my first post on this, way up at the top.
Yes Gord; I did; I'll check it but I'm not sure if the wiring is the problem. The other day when setting up the timing and since the car's tach was almost useless, Jjr and myself decided to just hook up a VDO tach he has laying around in the engine compartment to monitor engine speed. It worked perfectly without the needle jumping around, etc. One thing we noticed, though, is that the timing light was working erratically when hooked up to my car yet worked perfectly when hooked up to Jjr's car. Could it be an electrical problem? Otherwise the car works perfectly and the battery stays charged.
Where do you get power and ground connections for your timing light when on YOUR car??
Could be;
a poor ground for the light
poor 12V connection for your light
If you use the +12 side of the coil for timing light power, a poor connection at the coil (or at the other end of the ignition wire - dirty fuse connection, maybe?)
poor lead connection at the points or at the Disti side of the coil (should also have the tach connection at that same point)
Make sure BOTH the disti clamp nuts are tight - the one on the disti and the one on the case (for a solid electrical ground connection to the Disti).
If you're not using points (electronic module) could you swap the module with JJr's and see what happens? - it could be the module is "soft".
That's all I can think of for now......
gn
Could be;
a poor ground for the light
poor 12V connection for your light
If you use the +12 side of the coil for timing light power, a poor connection at the coil (or at the other end of the ignition wire - dirty fuse connection, maybe?)
poor lead connection at the points or at the Disti side of the coil (should also have the tach connection at that same point)
Make sure BOTH the disti clamp nuts are tight - the one on the disti and the one on the case (for a solid electrical ground connection to the Disti).
If you're not using points (electronic module) could you swap the module with JJr's and see what happens? - it could be the module is "soft".
That's all I can think of for now......
gn
Well Gord; everything's pretty clean in our cars (low mileage on them). Our connections went to the B+ at the alternator, the Kadron linkage whatchamacallit for ground and of course the spark plug wire for #1.