How can I tell if my Chevy ECM is running?

Turn the Chevy’s electrical system on, but leave the engine off. An active electrical system means the ECM will also be up and running. Count the flash codes and record them onto a sheet of paper. The check engine light will flash the codes at you, in a series of long and short pulses of light.

What was the problem with my 1994 GMC Sierra?

My 94 gmc sierra k1500 speedometer was acting up,brake light came on and it wouldnt shift into 3rd or od without slipping out of gear. Changed speedo sensor and cured all problems. 6 people found this helpful.

What kind of computer does a Chevy ECM use?

Chevrolet vehicles manufactured before 1996 use an internal computer called an Electronic Control Module, and it oversees the automated engine diagnostic routines. A Chevrolet’s ECM can sense problems as they present themselves, and it keeps an ongoing record.

Where is the jumper wire on a Chevy ECM?

The ALDL, for all General Motors vehicles, will be found directly below the steering column, in the center of the dash’s underside. Run a length of jumper wire between the ALDL’s “A” and “B” ports. These two slots are on the ALDL’s top row, and all the way to the right, at the end.

What’s the fuel Gage on a 1993 Chevy truck?

Fuel gage never wavered at 12-13 psi. MAP around 2.9v when PW 2.8MS when truck seemed to be falling a little flat under brake torque. This thing is really close to getting a carburetor on it.

Why does my 1993 Chevy TBI stall at idle?

Timing is steady and not jumping all over. It is a fuel issue. The only code that ever sets is a P044, lean exhaust, and the exhaust is really lean. We have swapped PCM/PROM with a same year Suburban, no change. Both vehicles run the same as this did using the other’s PCM.

What does the code 86 mean on a Chevy ECM?

Count the flash codes and record them onto a sheet of paper. The check engine light will flash the codes at you, in a series of long and short pulses of light. For example, General Motor’s code 86 will appear as eight long flashes, followed six shorter flashes. There will be a dark, silent pause between coding sets.

Are there any problems with the Chevrolet C1500?

Do not forget to read about Chevrolet C1500 problems, recalls and complaints . Find all the latest facts, figures and Chevrolet C1500 specs based on year, make and model. Chevrolet vehicle history report may contain the following information: title problems, prior damages, unsafe salvage rebuilds, odometer mileage, theft, past sales.

How to check the authenticity of a Chevrolet C1500?

This format was implemented by the ISO institute. Every car manufacturer is obliged to mark all its vehicles in this special format. This online service allows a user to check the validity of the car and get detailed information on almost any VIN number, search for Chevrolet C1500 car parts and check the car’s history.

What does the VIN number on a Chevrolet C1500 mean?

This is the Chevrolet C1500 VIN decoder. Every Chevrolet car has a unique identifier code called a VIN. This number contains vital information about the car, such as its manufacturer, year of production, the plant it was produced in, type of engine, model and more.

What kind of decoder does a c1500 have?

Chevrolet C1500 VIN decoder. Every Chevrolet car has a unique identifier code called a VIN. This number contains vital information about the car, such as its manufacturer, year of production, the plant it was produced in, type of engine, model and more.

How does a bad ECM affect fuel economy?

Poor Fuel Economy. A faulty ECM disallows your engine from knowing how much fuel to burn in the combustion process. Typically, the vehicle consumes more fuel than it should in this situation. You’ll end up paying more for gas than you would with a functioning ECM. The ECM plays a vital role in engine performance.

What should the fuel pressure be on a Chevy Cheyenne?

93 Chevy Cheyenne k3500, if it is running the Chevy vortec engine the fuel pump pressure is way too low, should be 56 psi+ depending on CSFI/CPI system or it will not start or open injectors, with out the aid of starting fluid. The factory manual specifies that the fuel pressure for the CSFI system should be between 56-62 PSI.

Can a bad fuel pump start a GM Spider?

If you need to test the ‘spider’ equipped GM pickups or SUVs, the following tutorial will help: Troubleshooting The Fuel Pump (GM 4.3L, 5.0L, 5.7L). A bad fuel pump will make your 4.3L, 5.0L, or 5.7L throttle body fuel injected pickup or SUV crank but not start. Here are some more specific symptoms:

What to do if your ECM is not connected to ignition?

Make sure that the red battery wire is connected to a battery source (It is highly recommended that this wire is connected directly to the battery) and the pink wire is connected to an ignition 1 source. If your ignition wire is not connected to an ignition 1 source your ECM will not be powered while cranking the engine. 3.

Where is the fuel pump relay on a 1987 car?

Locate the fuel pump relay, it is in the engine compartment, on the top of the firewall, next to the AC evaporator or where it would be if you don’t have AC. There should be a red wire about 6 inches long coming out of the plug on the bottom of the relay that is not connected to anything.

Where is the oil pressure switch on an 87 EFI?

On an 87 EFI system you will have an oil pressure sending unit and an oil pressure switch. The sending unit is located down by the oil filter and sends an electrical signal to the oil pressure gauge. The switch is on the top, back of the engine, almost under the distributor.

What kind of ignition system does a GMC Suburban have?

The typical ignition system circuit diagram for the 1992-1995 4.3L, 5.0L, and 5.7L 1500, 2500, 3500 Pick Up and Suburban can be found here: Ignition System Circuit Diagram (1992-1995 Chevy/GMC Pick Up And SUV).

What are the codes for GMC check engine lights?

P1245Intake Plenum Switchover Valve P1250Early Fuel Evaporation Heater Circuit P1257Supercharger System Overboost P1258Engine Coolant Overtemperature – Protection Mode Active P1260Last Test Failed SCC Or Theft Detected, Vehicle Immobilized

Can a bad ECM cause a car to stall?

Engine Stalling or Misfiring Erratic engine behavior may also indicate a bad or failing ECM. A faulty computer may cause the vehicle to intermittently stall or misfire. The symptoms might come and go and not appear to have any sort of pattern to their frequency or severity. 3. Engine Performance Issues

What happens when the ECM is not working properly?

When the ECM isn’t adjusting the throttle properly, shifting can feel herky-jerky, as if you’re in the car with a first-time driver learning to work a stick shift. 6. Your Engine Shuts Off for No Reason This is another symptom of an improper fuel-to-air ratio.

Can a knock sensor cause a car ECM to fail?

There’s also a knock sensor on the engine itself. While these sensors aren’t likely to cause any catastrophic problems, failures in these areas can cause your ECM to make unnecessary adjustments that affect your car’s performance. In these cases, though, the problem is usually with the sensors, and not with the ECM.

How does the ECM work on a Chevy truck?

Every Chevrolet truck has an engine control module that manages the electronic components of the engine and monitors sensors for errors. Returning the ECM to its factory state may be necessary to troubleshoot or resolve a number of problems. Step 1 Remove the nut from the negative battery cable using a socket set or wrench.

Can a bad ECM cause a stick shift?

The ECM doesn’t control the transmission on a stick shift, so if you’re having problems with your five-speed, it’s the transmission. If you’ve done numerous repairs on the transmission and replaced your automatic transmission fluid and you’re still having problems, the ECM could be at the root of your problems.

What to do if your car ECM is not working?

The only way to be sure is to visit a mechanic with the proper computer. They can analyze your vehicle’s error codes, and let you know exactly what the problem is. If your ECM can’t make adjustments to your car’s timing or air to fuel ratio, the vehicle may not start at all.

How can I tell if my Chevy ECM is running?