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How to solve g3520 detonation - 1987 GMC G3500

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Seatbelts locked up after crash

They have deployed the seat belt tensioners! These are similar to the detonator on the airbags! You will have to replace the detonators and probably reset the dash lights too!

Nov 14, 2014 | Cars & Trucks

1 Answer

2010 dodge nitro detonator has no heat.

You ave a bad actuator in the dash. Take it to your dealer they should warranty it. Dodge has had a huge issue with all the hvac actuators in the dash.

Dec 06, 2013 | 2010 Dodge Nitro Detonator

1 Answer

Loss of power and engine making rattling noise

Run fault codes and look for failed knock sensors. I would suggest that the rattling noise is detonation from a lean fuel mixture-ignition timing or faulty EGR system. Detonation is when the fuel ignites with out the use of spark and occurs early as the piston is coming up so the piston is slammed against the cylinder walls. Prolonged detonation will cause melted holes in the pistons tops and broken rings so I would advise you fix this problem as soon as possible.

Sep 01, 2013 | GMC Cars & Trucks

1 Answer

Engine detonation on 98 k1500

what do you call detonation you are talking about explain detonation.

Apr 19, 2013 | 1998 Chevrolet K1500

1 Answer

92 chevy s10 code says esc module

What is electronic spark control (ESC)?

Electronic Spark Control

An additional electronic control (ESC) is used on vehicles equipped with
an LE9 engine. The Electronic Spark Control (ESC) system is a closed
loop system that controls engine detonation by modifying the spark
advance when detonation occurs. The amount of retard is a function of
the degree of detonation.


The (ESC) controller processes the sensor signal and applies it to the
distributor to adjust spark timing. The process is continuous so that
the presence of detonation is monitored and controlled. The controller
is a hard wired signal processor/amplifier which operates from 6 to 16
volts. The controller has no memory storage.


The (ESC) sensor is a piezoelectric device, mounted in the engine block
that detects the presence (or absence) and intensity of detonation by
the vibration characteristics of the engine. The output is an
electrical signal that goes to the controller. A sensor failure would
allow no retard.

ESC Vacuum Switch

On LE9 engine equipped vehicles with automatic transmission a "tip in"
vacuum switch is used. Its function is to provide a momentary contact
closure (signal) to the ESC controller during a throttle "tip in"
condition which then briefly retards spark timing to minimize knock.
The switch contacts are normally open under steady engine vacuum
conditions including no vacuum, and all brief increasing vacuum
conditions. Basically the switch closes only during rapidly decreasing
vacuum conditions such as that encountered on rapid throttle operation.

Dec 18, 2012 | Cars & Trucks

2 Answers

What is a knock sensor

here goes for a 1 Tu. this sensor detects detonation in the engine caused by a dirty piston head dirty valves and valve train. When it detects this detonation it tells the computer to ****** the timing so it does not burn a hole in the pistons, at the same tie it tells the computer this the computer adjust the fuel mixture ratio to decrease hot soak detonation which can occur after running the engine getting it hot and turning it off for 5 minutes and causing the gas to pre ignite due to the heat of the engine. This device is made of piezoelectric material which generates a voltage due to sound running threw the knock sensor, Ceramic disks wafered together and it has a preset low and high voltage low voltage is 1.0 DC VOLTS high is 4.0 volts dc WITH 5 VOLTS DC as a reference voltage for testing purposes. to see if it is working tap near the knock sensor and if it is working you will notice a variation in the running of the engine as it changes timing and fuel mix to stop detonation.

Apr 03, 2010 | 1999 Isuzu VehiCROSS

1 Answer

2003 yukon xl with strong knock and flashing check engine light on moderate acceleration

Here is an explanation of the "knock".

Abnormal combustion (Detonation)
When unburned fuel/air mixture beyond the boundary of the flame front is subjected to a combination of heat and pressure for a certain duration (beyond the delay period of the fuel used), detonation may occur. Detonation is characterized by an instantaneous, explosive ignition of at least one pocket of fuel/air mixture outside of the flame front. A local shockwave is created around each pocket and the cylinder pressure may rise sharply beyond its design limits. If detonation is allowed to persist under extreme conditions or over many engine cycles, engine parts can be damaged or destroyed. The simplest deleterious effects are typically particle wear caused by moderate knocking, which may further ensue through the engine's oil system and cause wear on other parts before being trapped by the oil filter. Severe knocking can lead to catastrophic failure in the form of physical holes punched through the piston or head (i.e., rupture of the combustion chamber), either of which depressurizes the affected cylinder and introduces large metal fragments, fuel, and combustion products into the oil system.
Detonation can be prevented by any or all of the following techniques: the use of a fuel with high octane rating, which increases the combustion temperature of the fuel and reduces the proclivity to detonate; enriching the fuel/air ratio, which adds extra fuel to the mixture and increases the cooling effect when the fuel vaporizes in the cylinder; reducing peak cylinder pressure by increasing the engine revolutions (e.g., shifting to a lower gear); decreasing the manifold pressure by reducing the throttle opening; or reducing the load on the engine. Because pressure and temperature are strongly linked, knock can also be attenuated by controlling peak combustion chamber temperatures at the engineering level by compression ratio reduction, exhaust gas recirculation, appropriate calibration of the engine's ignition timing schedule, and careful design of the engine's combustion chambers and cooling system. As an aftermarket solution, a water injection system can be employed to reduce combustion chamber peak temperatures and thus suppress detonation.

Jun 26, 2009 | 2003 GMC Yukon

1 Answer

1983 buick regal limited-where is the detonation sensor located

Usually on the side of the block...don't remember seeing one on 83's though.

Jun 19, 2009 | 1983 Buick Regal

1 Answer

Where or what is a detoneation circuit

The detonation sensor is usually located on the side of the engine block - it is a cylindrical sensor that screws into the side of the block (and has one electrical conection) that picks up engine detonation and relays that back to the ECM to ****** the ignition timing when "spark knock" occurs. I'd bet the Air Flow meter is the culprit however, det sensor rarely go bad....

Jan 31, 2009 | 1993 Nissan Pathfinder

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