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Discussion Starter · #1 ·
hey javad,I changed my fpr to a correct 5cyl unit to see if i could correct my tach reading,but huh,the car won't run with that relay,I know it's the proper relay as I got it out of a 5k( the gray one with the fuse port in it).i did with one other relay i had and it did the same thing too.any thoughts.I noticed the gray relay had two extra smaller pronges than the one i replaced.could i have accidentally hooked up something wrong to have this happen ?
 

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Hey Derek, hmm, not sure, I usually don't use the stock relays, but just make sure you've pinned out the relay correctly, did you just plug this into your stock fuse block under the hood? You should determine what isn't getting power with that relay connected, that will give you some insight.
 

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What kind of car is this all going on in? I forget.... :p

If it's a T89 chassis then the stock FPR should have already been the gray style with the fuse fitting on top. There is no distinction in these relays to being 5 or 4 cylinder, they are switched on and off via the ECU's

If this is in a 4kq/T85 then the relay normally gets it's 'on' signal from the coil ground pulse, and if you swapped it out for the later style ones with the fuse then the fuel pump will never turn on, it's not seeing the correct inputs (it needs a solid "Ground" signal from an ECU not a pulsing coil signal that is being sent to it. These relays are specific the the 4 and 5 cylinder cars, as they have the rev limiter built into them, and count the number of ignition pulses to determin crank revs. So a 4 cyl FPR will have it's redline cutout at 4/5ths what is should if being used on a I5 motor. So your 6800 limit would become ~5400, for example.

Anyway, what kind of car is this on again, and how are you trying to setup your FPR, computer controlled, or coil?
 

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Discussion Starter · #4 ·
my car is a type 85. the whole problem here is that my dash tach reading is erred,at idle my tach reads about 200 rpm higher than the 034 ecu shows on the computer screen,and it gradually gets farther out of whack as the rpms go up,like at my 034 rev limit of 6800,when the motor cuts out at that limit the dash tach is reading somewheres around( i'm guessing cause the tach doesn't go that high) 8500,wrestling with the clock needles :p . the fpr I have in there is K A E unit.it doesn't have the small L and T pronges that are on either side of the #30 power pronge on the gray audi relay. I don't recall having an erred tach reading before I did the turbo install. I also have tried hooking up the tach to the mac 11 tach output,but got the same erred reading,It's driving me :bashtard:
 
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