Ok so I know everybody on here is going to tell me that I need a new ignitor but the honda dealership already replaced it, along with most of the distributor. They have had it numerous times in the past month for the same problem and they keep saying they fixed it, only to see it back in about a week with the same problem. Is there anything else it could be besides the ignitor or the coil or all the other stuff they have replaced such as cap, wires, etc.? I'm really at a loss and I think honda is too. I know they are retarded and I shouldn't have taken it there in the first place but I don't really know anything about cars. The only reason I keep taking it back is because I refuse to pay them more money but they keep giving me parts. Any help would be greatly appreciated, I'm really upset over this whole issue and I wanna sell my lude because it has been nothing but trouble. With winter coming I think thats a bad idea but I atleast need to get it fixed before I sell it.

 

is it the tach just bouncing or is the engine revving in sequence with the bouncy tach? more info...

 

My car does the same (if it's just the tach bouncing, and not the engine?).. If I coast in a gear at 6000 RPM, my tach jumps between 6000-7500 and my shift light flickers (set at 8200 RPM).

I was going to get a spare dizzy just in case it's going out... but I don't know if that'll fix it.

 

Please explain yourself if you want us to help. You did not state your problem at any time during your post.

 

the tach jumps when i get the engine really hot. It used to lose engine power but since they replaced all that **** only the tach has jumped i havent noticed a loss of power yet but ive only gotten it hot enough for the tach to jump once since ive got it back.

 

Check ur main relay. When that's going out it makes ur tach bounce, try flicking ur main relay while ur cars on and see if it makes ur tach bounce.

 

well i have a 4th gen so i'm not sure if it will work on the 5th or not. You sound like me when I had this problem. I can take a pic tomorrow afternoon if you need it since my throttle body and intake manifold are laying int he office. (it will be after work)

There is a small plate ont he back of the throttle body with 2 screws. If you pull this plate off there is a plastic valve and a spring. It has a line acorss it and looks like a big screw. It should be tight and not loose where its touching the plate.

I screwed mine back down and haven't had a single problem since.

this was posted on the old preludeonline.com forum after I had the prpblem when i first bought my car.

 

could be a cold soldering point that needs to be touched up. preludes are notorious for bad electrical problems cause of bad soldering. when your car warms up, it causes the points/wires to expand/contract and have flaky connections. (main relays, climate control boards, etc)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Razer &raquo;</TD></TR><TR><TD CLASS="quote">There is a small plate ont he back of the throttle body with 2 screws. If you pull this plate off there is a plastic valve and a spring. It has a line acorss it and looks like a big screw. It should be tight and not loose where its touching the plate.

I screwed mine back down and haven't had a single problem since.
</TD></TR></TABLE>

I'm guessing your idle was jumping up and down? It sounds like the OP is just having the tach, and not the engine, bounce up and down.

(Mine does that, any way)

 

my car idles fine, really the only problem now is the tach still jumping. it used to lose power in lower gears but i havent noticed that problem since they replaced all that stuff for me. its hard to say tho because it only happens when ive been driving the car for a while and i get it really hot. recently i havent had time to go out and drive for a long time and it hasnt happened recently because ive been driving short distances. when i do go out tho i try to drive it kinda hard to see if i can get it to happen but it doesnt.

 

This is a good thread because people are listing all the things that could possibly go wrong with your tach. There are several different things it could be, starting with the distributor and going all the way up to the gauge cluster itself. It sounds like your problem is in the gauges.

In my own case, I've had the jumpy tach problem ever since I bought my car, which is a year and a half ago. Now my speedometer is having the same problem, plus the tach jumps even if the engine is off, so I know it's electrical.

The only specific thing I've heard that hasn't been mentioned here yet is a bad solder behind the cluster itself. Pull the cluster out and check for that before you throw in the towel and sell your nice Prelude because of a jumpy tach.

 

haha thanks for the info but my prelude is not nice. i shouldnt have bought it but i wanted a car so bad because i was without one for about 2 months. i drove about an hour and a half to look at it and just said expletive it and got it. bad decision, it needs some minor body work, interior has cig burns, has some honda cancer because i removed the weather stripping it was never removed before. Plus i want a new paint job and the rims arent as nice as id like them to be either. not to mention this never ending tach problem which i also think is electrical.

 

Does ur engine rev all the way to redline? I had an annoying problem for months where my tach would bounce and cut out at 6500 rpms, finally after months I found there was a crap load of corrosion on my battery terminal, messing with the ground, cleaned that up and haven't had a problem since. It's a long shot but a real quick check.

 

hey check your ground wires all of them and especially the big ground wires below your thermostat housing thouse are the ones to your ecm and cause your tach to jump like mine....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by invasian_boy &raquo;</TD></TR><TR><TD CLASS="quote">hey check your ground wires all of them and especially the big ground wires below your thermostat housing thouse are the ones to your ecm and cause your tach to jump like mine....</TD></TR></TABLE>
Hey that's a good idea. I'll make sure and get that done (since I was gonna do it anyway sometime).

 

One thing i forgot to mention is that it usually starts when i'm on the highway after i have been driving it for a while. It doesnt necessarily mean that i was going super fast on the highway but it starts when i'm in 5th gear on the highway after i have already got the engine hot. After i get off the highway the tach continues to jump in other gears. After i let the car cool down it is fine. It's only happened a few times since its been to the dealership to get all that previously described work done. Im going to get the ground checked out but besides that i dont have any other ideas.

 

Sound like it could be a loose connection or sauder since it only does it when the engine is fully warmed up. Not sure but something to check.

 

a loose ground connection? or what kind of connection?

 

Could be a ground but unlikely since only ur tach is having problems. Could be connections on ur ignitor, or somewhere else. When it bounces does ur car sputter or bog or does it seam to drive just fine?

 

before they replaced the ignitor and a bunch of other ignition stuff it did sputter but now it only seems to jump. today it was weird though it started jumping right after i started it up, wasnt jumping in 1st and 2nd but once i hit third it started jumping immediately. it was a very short drive across campus so i never even went higher than 3rd but it was weird how it was jumping right after start up, it usually took forever to get it to jump after they replaced all that stuff. the only thing i can think of is that the headlights were on, the rear defroster was on ,the front defrosters were on high, and my wipers were on because my car was covered in rain and condensation. i had to come back to my place to study but tomorrow i should have some time to take it out and see whats up but its annoying the hell outta me and im probably gonna sell it because im sick of dealing with the problems of it.

 

Another thing ive noticed recently is that when i start up the car i hear a terrible vibration noise coming from the engine bay(not exactly sure where) and it gets worse when i give it some gas. Im pretty sure it stops when i get it into third gear but in first and second it sucks. It also seems like it wants to stall when i take my foot off the gas in 1st or 2nd. I dont know if this would be related to my tach jumping but its just another problem that pisses me off. Any help is greatly appreciated guys.

 

Any more help?

 

I'm still kind of confused about the symptoms of your problem. Is the needle in your gauge jumping up and down randomly NOT corresponding with your engines RPM's or is it the engine itself that is revving up and down?

If its just the tach needle fluttering it could be a bad connection in the signal wire between the gauge in your dash and the distributor(normally the wire is blue.) I had this problem once and it turned out that the female connector on the tach signal wire had worked off the male post under the distributor cap.

-Long story short.... Pull off your distributor cap off and find the blue tach signal wire, make sure it is securely connected to the post, if it is, trace it back to the gauge in the dash until you find a cut in the wire or loose connector.

Hope this helps....
parker

 

I have the same probelm with my car (4th gen VTEC) the tach bounces only when its hot outside 80+ I dont have the problem in the winter time at all, the speedo bounces as well. This still happens even after my JDM h22a was installed.

 

yo dude, you know what? right now im having the exact same problem as you. I know exactly what you talking about. So far what i havent hear anyone saying is the ignition module is bad. I have a couple mechanic friends suggested. for me, i havnt have time to test it out. So Copeman, try to see if honda can test your ICM, that could be your problem. And let me know if thats is it, while im doing my own testing right now.