slownrusty Posted October 26, 2008 Share Posted October 26, 2008 Wow...so I have been chasing this problem for weeks and need some feedback. I installed: 1) AEM Uego Wideband 2) Autometer Electric Water Temp Gauge (with Data Logging) 3) Autometer EGT Pyrometer. All nicely neatly wired with switchable power taken from the fuse panel and all good grounds. With all gauges installed, the car will NOT rev past 2500rpm under load, in neutral it revs just great. I pulled out all the gauges I installed today in frustration and the car returned to normal, revs great all the way well past 2500rpm. So evidently, these gauges are giving some kind of "noise" "frequency" "intereference" that is upsetting the factory computer. So what to do? I am thinking some kind of metal based sheathing tape to eliminate this interference over these cables. Any other ideas? Does anyone know where I can get this type of sheathing? I Google'd - nothing, checked Home Depot and Radio Shack on line and nothing. Glad the car is running normal again, but sucks that I have $500 in gauges sitting on my work bench that cannot be used Please help, especially you electrical gurus and whizs! Yasin Quote Link to comment Share on other sites More sharing options...
TimZ Posted October 26, 2008 Share Posted October 26, 2008 Wow...so I have been chasing this problem for weeks and need some feedback. I installed: 1) AEM Uego Wideband 2) Autometer Electric Water Temp Gauge (with Data Logging) 3) Autometer EGT Pyrometer. All nicely neatly wired with switchable power taken from the fuse panel and all good grounds. With all gauges installed, the car will NOT rev past 2500rpm under load, in neutral it revs just great. I pulled out all the gauges I installed today in frustration and the car returned to normal, revs great all the way well past 2500rpm. So evidently, these gauges are giving some kind of "noise" "frequency" "intereference" that is upsetting the factory computer. So what to do? I am thinking some kind of metal based sheathing tape to eliminate this interference over these cables. Any other ideas? Does anyone know where I can get this type of sheathing? I Google'd - nothing, checked Home Depot and Radio Shack on line and nothing. Glad the car is running normal again, but sucks that I have $500 in gauges sitting on my work bench that cannot be used Please help, especially you electrical gurus and whizs! Yasin First thing I'd recommend is to install one at a time and see which one is causing your problem. Much easier to diagnose this way. Quote Link to comment Share on other sites More sharing options...
slownrusty Posted October 26, 2008 Author Share Posted October 26, 2008 That is my plan and makes sense Tim, will do that and see which one is the culprit. Regards - Yasin Quote Link to comment Share on other sites More sharing options...
Sparky Posted October 26, 2008 Share Posted October 26, 2008 As Tim suggests, wire in one at a time to find the trouble gauge(S) My personal bet is on the wideband. Make sure your not grounding the gauges at a common point with the ecu, You can easily ground the gauges to a floating block and from that install a lead that will allow you to ground to different points, be sure to power off before swapping grounding points to avoid damaging the gauges. If at any point in your wiring, you wrap, or loop any of the wiring for the gauges around some of the ECU wiring your concentrating EMI interference...it may not actually appear to be perfect loop, even a very gradual spiral type wrapping of wires can exasperate the issue. Wire the gauges on their own power circuit, route the 12V supply away from any sensitive wires. After that should the problem still occur, re-wiring the sensitive wires with shielded wiring will be your next step, the dizzy leads are already shielded but the TPS and AFM are not. good luck! Quote Link to comment Share on other sites More sharing options...
ktm Posted October 26, 2008 Share Posted October 26, 2008 Yasin, you will need to buy the sheathing either on-line or from a commercial grade electrical supply store. Quote Link to comment Share on other sites More sharing options...
JSM Posted October 27, 2008 Share Posted October 27, 2008 I thought you had it fixed w/ removing the wideband? Quote Link to comment Share on other sites More sharing options...
slownrusty Posted October 27, 2008 Author Share Posted October 27, 2008 Sparky - I gounded all three gauges together with a loop connector (that a bolt goes through), I tried grounding at the battery - no luck, then even tried one of the valve cover bolts - no luck either. Should I try grounding each gauge separately, instead of tying them all together? Can you please show me what a floating block looks like? Is it like this??: Bo - Yes I am looking at local Electrical supply places in town for good sheathing. JSM - not quite! Regards - Yasin Quote Link to comment Share on other sites More sharing options...
Sparky Posted October 27, 2008 Share Posted October 27, 2008 Sparky - I gounded all three gauges together with a loop connector (that a bolt goes through), I tried grounding at the battery - no luck, then even tried one of the valve cover bolts - no luck either. Should I try grounding each gauge separately, instead of tying them all together? Can you please show me what a floating block looks like? Is it like this??: Finding the right ground source can be tricky as certain cars react in different ways...where is the battery ground to? engine block? firewall? starter? have you checked your engine to chassis ground wire? As you add more and more components to a system a weak point can develop as they pull ground. As far as the floating block goes, yeah what you've got pictured is what I'm talking about, just an insulated connector or bridge. you can use that to tie all the gauges into so that it doesn't accidentally ground out somewhere else, you could also just as easily use electrical tape and some alligator clips to test grounding points out, I just like the blocks to keep things tidy and organized. You did mention that you've already tried multiple grounding points so I'm wondering if the issue is something else. I would install one thing at a time, being very aware of the wires around it. Find the component that's causing the issue and the go from there. I don't remember this from your other post but how is your alternator? are you seeing a voltage drop at the ECU when the problem starts? I can't imagine that three gauges are pulling enough amps to cause a voltage drop but if the alternator is failing the smallest draw can amplify the issue. Quote Link to comment Share on other sites More sharing options...
slownrusty Posted October 27, 2008 Author Share Posted October 27, 2008 Thanks Sparky! Very helpful reply. My alternator is cheapie from Autozone (dare I say) that I bought 6+ years ago, I might change it anyway. I will go ahead and buy the grounding block as Radio Shack sell them for a couple of bucks. My battery is grounded to the actual battery tray and then the starter is also grounded to that point, its a threaded holde that a 12mm bolt goes through. I haved added one of those Sun Grounding kits to the car as well, to improve the engine to chassis grounds. Will report back soon! My best - Yasin Quote Link to comment Share on other sites More sharing options...
shift00 Posted November 21, 2013 Share Posted November 21, 2013 Did the alternator fix your problem? Quote Link to comment Share on other sites More sharing options...
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