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electronic spark timing is your distributor.
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What does the number 42 mean in the trouble codes to a 1994 Chevy suburban?
Electronic Spark Timing (EST) circuit is shorted to ground.
1993 Chevy astro van 4.3 error code 41?
Code 41 - EST Circuit (Electronic Spark Timing) or CMP Sensor, No distributor Reference pulses to the PCM at specified engine Vacuum, A malfunctioning ignition module can very easily cause this code to set. If the EST circuit is either open or grounded it may very well cause the same problem. Hope this helps.
Where is the est wiring on a 98 Chevy truck 5.7 liter?
That year did not have a EST/ electronic spark timing connector. The timing is controlled by the PCM / Powertrain Controll Module. It requires a engine scanner to ajust the timing. You can not use a timing light.
How can you fix a 93 Geo Storm that stalls when driving and is giving a code 42?
Electronic Spark Timing (EST) bypass circuit or EST circuit is grounded or open. HEI Module may be the cause
How can you fix code 43 on 1987 Chevy truck?
Code 43 = Electeroic Spark Timing (EST) circuit low voltage detected OR ESC circuit problems. Without being there to put a meter on different components and check it out, all I can do is point you to the electronic spark control module.
Where is firewall ground wire located on 305 Chevy engine?
Où est le fils de sol pare-feu situé sur 305 Chevrolet moteur
What does est stand for on a Chevy truck?
electronic spark timing connector
Where is the EST Circuit on a 1987 2.5 Chevy S-10 located?
According to my repair programs at my shop there is no actual connector for the est.To set the timing you need to short'a' and 'b' of the dianostic connector.I use a paper clip bent in a 'u' shape.Tool manufacturers do make a key to plug in but it does the same thing.With the engine running you can set the timing.With the engine off and the key on this will blink the check engine light for any stored codes in you computer system. whitegorilla@yahoo.com
What is The appropriate EST for performing a resistance test on a potentiometer-type TPS isolated from its circuit?
DMM
What does the est on a 89 Chevy astro do?
have a 89 Chevy astro van starts good till warms up the start to chock and then stalls
GM Scanner found code 42 EST How do you fix it?
The EST circuit has been on G.M. vehicles for quite a few years. So, EST can be seen on a vehicle with a high-energy ignition distributor (HEI) or, vehicles that are equipped with a direct ignition system. (DIS) {Distributor �less}Why EST?To provide improved engine performance, better fuel economy, and to better control exhaust emissions, the computer controls spark advance (timing) with the EST system. To calculate spark advance the computer uses information from the manifold absolute pressure (MAP) sensor and the coolant temperature sensor (CTS) as well as engine RPM.How spark advance is calculated:� Low MAP (low engine load) = more spark advance� Cold engine = more spark advance� High MAP (high engine load) = less spark advance� Warm engine = less spark advance� High RPM = more spark advance� Low RPM = less spark advanceThe system.The EST system consists of the ignition module, computer (ECM/PCM), and the connecting wiring. There are four circuits to this system.The circuits and their functions:� Reference.This circuit provides the computer with RPM information. If this circuit becomes open or shorted to ground the engine will not run, because the computer will not operate �trigger� the fuel injectors.A common saying here is, no reference no run.� Reference ground.This circuit is grounded in the ignition module and the computer; it makes sure the ground circuit has no voltage drop, which could affect vehicle performance. I have found an open in this circuit can cause a vehicle �no start� as well as a false code 42/E23.� By-pass.The computer applies 5 volts to this circuit to switch timing control from the ignition module to the computer. The computer is telling the ignition module that it will control the timing. An open or a short to ground of this circuit will set the code and the engine will run on base timing. (Plus a small amount of advance built into the ignition module.)� EST.This circuit triggers the ignition module. The computer does not know what the actual timing is, what it does know is when it gets a reference signal. It uses this reference signal as a base point and advances or retards the spark from that point. So, if on vehicles where the base timing is adjustable, and the base timing is set incorrectly, the spark curve will be off through its entire range by the amount that the base timing is misadjusted. An open or short to ground in this circuit will set the code and cause the engine to run on ignition module timing.Why the computer flags this code.What we have here is a failure to communicate.� The ignition module and the computer are in constant communication when the engine is in operation. (Over 400 RPM.)With the computer telling the module the correct timing. If communication is lost or a circuit becomes infected with false signals (bad grounds, short to battery +, Electro Magnetic Interference {spark plug wires to close to circuit wiring}, oil contamination of the circuit connectors and wiring) then the computer will turn timing control back to the ignition module and flag the code.Possible causes:� EST circuit open or grounded.� Bypass circuit open or grounded.� Reference Ground circuit open or shorted to battery� +.� A bad computer to engine circuit ground.� A defective ignition module.� A defective computer. If you are testing a vehicle for this code check the routing of the spark plug wires making sure they are not to close to the EST circuit(s) wiring. Check the connector terminals making sure they are not over-sized or oil contaminated. Check the entire wiring of the circuits for chaffing,short(s) ground.Http://www.Freeautomechanic.com
How do unhook est on a 1995 Chevy 2500?
Why would you want to unhook the Electronic Spark Timing?
