JMS Fuel Max Failure

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Tomkirkland4

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I have had the JMS FuelMax installed on my truck for about 600 miles and it recently failed. The truck was randomly losing fuel pressure causing my check engine light to come on and sudden loss of power. Yesterday it wouldn’t start after driving it for a few miles. I disconnected the JMS unit which resolved the issue. Luckily I only need the unit for running E85 and my tank had 93 in it. Anyone else have a similar issue with JMS? I’ll be sending it in for repair or switching to a new low pressure fuel pump.
 

TwizzleStix

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The JMS is a basic voltage booster, so it has at least one transformer, several diodes, and likely a basic controller for the sensor used, if any. A solid ground connection is crucial for reliable operation as well. Check all the wiring and if it’s all good, maybe it has some warranty. Who installed and set it up? Thats where it needs to go back to for diag.
 
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