Q: 1997 GMC Safari SLX 4.3L I Just install a coolant temp sending unit. now my motor wont start. but dose when unplug. what could be

asked by on

1997 GMC Safari SLX 4.3L I Just install a coolant temp sending unit. now my motor wont start. but dose when unplug. what could it be
My car has an automatic transmission.

The coolant temperature sensor sends a signal to the ECM to enrich the mixture when the engine is cold (cold engines need more fuel at initial start up), otherwise you will have hard starting or perhaps no starting. Something is wrong in that sensor circuit such that when the sensor is in the circuit, as it should be of course, the computer is either receiving, or generating, the wrong signal. It could be a wiring fault issue. If you have the factory wiring diagram, you can look at the logic on the diagram, measure for voltage and continuity, check the ground(s) and so forth and possibly track it down. If you do not have the factory wiring diagram simply request a sensor circuit diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. 1997 GMC Safari SLX 4.3L I Just install a coolant temp sending unit. now my motor wont start. but dose when unplug. what could be

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Rough/ low idle, smells rich, and has a knocking sound near rear (like exhaust is rattling).

Hello. This may be potentially related to the mass air flow sensor or throttle position sensor. Initially, it may have been a faulty O2 sensor, but now since that has been replaced, that part of the system should work correctly....

Q: Steering going out

Intermediate shaft issues are common on Dodge Dakotas. The symptoms you described are very typical. The shaft tends to bind at times and make clunk sounds when going over bumps and turning. The repair is simply to replace the shaft....

Q: Q: Key stuck in ignition switch

I believe the part you might be referring to is not the ignition switch but rather the lock cylinder. The ignition switch as an actual electronic switch located further down the steering column on your vehicle. The lock cylinder is...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.