Backfeed from starter wire?

[Jr. Roy]

i have the alcohol interlock device installed in my truck and in the last month somehow their relay got fried 3 times i kept taking it back and insisting it was their equipment, now after it got taken to the head office, they told me there is a backfeed coming from the starter wire. (their equipment is directly conneted to it.) they told me they cut it open and on the key side of the wire reads 12.17 v when the key is turned to crank , but reads 10.55 v when the key is to the run postion (he said igintion, but i assume he means run )
and this is likely frying their relay.
any ideas what could be causing this backfeed? could a faulty ignition tumbler be to blame?
i went through 3 relays and i was told any further problem would be caused by my truck so i'm basically cut off and work be getting anymore work or relays for free.

 

[Hewgull]

Usually a relay goes because of too much amperage that the relay isn't able to handle. Does their relay replace the factory starter relay so that when the device says its ok to drive it activates letting power go to the starter?

 

[kimcrwbr1]

I suppose it could be the ignition switch, computer or wiring. The tfi ignition module and computer have a run and start circuit. If your getting power to the small start wire on the start solenoid with the key on run pull that wire off and see if it is backfeeding thru the solenoid if not connect it back together and disconnect the TFI module on the dizzy if you no longer get power to the solenoid it is likely the module. If you disconnect power to the blow and go they will send a report to the DMV that you were tampering with the machine be careful.

 

[kimcrwbr1]

All they do is cut the start wire and the device closes the circuit when you pass the test with a relay. When you turn the key to start it closes the start solenoid and retards the ignition timing for a quick start. If there is constant power to the red/ltblu wire on the ignition module I believe it is the third wire from the top of the connector then your engine is probably not advancing properly anyway. You can change it without disconnecting the battery I just recommend getting a good module from napa and use plenty of heat sink grease when installing it. You can get the thin wall socket you will need to remove it at any part store.

 

[adsm08]

Have you tried not drinking and driving? I hear that fixes most of the problems with those stupid breathalizer things.

 

[kimcrwbr1]

I have been sober over 5 years and that logic dont work for this alcoholic. If I drink I drive drunk did so for over 30 years. My only option is not to drink period. Then I know I will never have to pay for another blow and go. AA works just fine for me!

 

[cody93]

why did i have a vision of someone who is hammered push starting his truck to by-pass the device? well, if ur wasted, it'll seem like a good idea...

 

[Jr. Roy]

Usually a relay goes because of too much amperage that the relay isn't able to handle. Does their relay replace the factory starter relay so that when the device says its ok to drive it activates letting power go to the starter?

no, their relay doesn't replace the starter relay its in the cab under the dash, interupting the starter wire and only connecting the circut once the device gets a clean blow test

 

[Jr. Roy]

im worried about blowing another relay, was told i would have to pay out the 250.00 deductable if it went again, gonna get Jr. towed up here and im leaning towards replacing the starter : the bearing was quite worn when i bench tested it, thought it might be needing too much juice and thusly frying the relay,
Ignition tumbler sometimes is "frozen" in off i have to work it back and forth to get it to turn so i reckon that its pretty shot and might have some loose wires that are causing a short, so im probly gonna go get a new one of those.

 

[Jr. Roy]

All they do is cut the start wire and the device closes the circuit when you pass the test with a relay. When you turn the key to start it closes the start solenoid and retards the ignition timing for a quick start. If there is constant power to the red/ltblu wire on the ignition module I believe it is the third wire from the top of the connector then your engine is probably not advancing properly anyway. You can change it without disconnecting the battery I just recommend getting a good module from napa and use plenty of heat sink grease when installing it. You can get the thin wall socket you will need to remove it at any part store.

thing is the truck starts runs fine when a new relay is put in and even when the mechanic barred two wires it the alcohol interlock relay harness and 'hotwired" it

 

[Jr. Roy]

Have you tried not drinking and driving? I hear that fixes most of the problems with those stupid breathalizer things.

thanks for the tip boss