#Fuel injector oscilloscope pattern code#

More data parameters to use, faster refresh rates and better graphing all have played a role in making scan tool diagnostics easier. Modern scan tools, both OEM and aftermarket, have come a long way. Fuel Injectors fuel pumps fuel pump diagnosis fuel pump diagnostics digital storage oscilloscope DSOs using DSOs fuel systems repair shop repair shops automotive aftermarket Live data is of all importance to make the diagnostics of the vehicle easier and more accurate.Using a Digital Storage Oscilloscope to test fuel injectors adds depth to your fuel system diagnosis. Same is true if it pegs at like 250 degrees. With it being 90 degrees outside, the car is running very rich and sets an oxygen sensor code, but not engine temp code. If the sensor goes bad and sticks at a value like -30 F degrees, the computer reads the value as still in the range of operation and adjusts the fuel accordingly.

At least on the vehicles that I am familiar with.

#Fuel injector oscilloscope pattern code#

The computer will not set a code between those two values. The reason for this is the operating temperature design specified range for the sensor readings would be between -40 F degrees to +256 F degrees.

The real cause of the light & code is a bad engine temperature sensor, but no codes for the temp sensor. The cause of the code is not the oxygen sensor in this case. Depending on the vehicle it might just say oxygen sensor or maybe rich or lean sensor. A simple 'code reader' from the local auto parts store may not help a lot.Įxample: You have a car that is getting poor fuel economy. The knowledge and experience of the technician with UNDERSTANDING the vehicle systems is all important. I would add that a word of caution is needed when trying to find a problem with a car. Back then if you looked inside the distributor and found one with a rubber plug that was colored black (instead of gray or beige or whatever) you were supposed to replace it on sight! Not easy to get out either, with the distributor gear pressed and pinned on. Oldtech: If you mean the pickup in the distributor, there was a rash of bad ones. All a scan tool did was make it easier to trigger the internal tests. In the 80s and 90s there was about a 75-80 percent chance it would be something else.įords in those days had EEC-IV engine controls and, unlike the systems used on most other makes, the diagnostics routines were all built into the ECM. Then you would investigate what the ECM saw (the computer was often called an ECM in those days) that it thought was bad enough to tell you about.Įxample: Today if you see a code that says 'oxygen sensor', there is a very good chance the oxygen sensor is bad. Then, you would look at the part, the wiring, etc. The code you read would just point you to which circuit to go looking at. I know it often works today, but back then it did not. You didn't just read a code in those days and have the scan tool tell you what to replace. Once set up though, it works as well as analog.

It is a far cry from pulling 3 leads out of an over head boom and having a pattern on the screen (as would happen with an analog automotive ignition scope). It is a wonderful lab scope for automotive work, but isn't very quick to set up for distributor ignition. I have a fluke 98 that is a lab scope with attachments and modes to view distributor ignition patterns. Some tools exist that are built for the automotive trade and are intended to do both. A digital one will be fine, and probably a better choice, as long as it is modern. Why? Because most digital ignition scopes sold for automotive diagnostics in that era (1980s-1990s) were close to useless.įor troubleshooting electronic engine controls, sensors, fuel injection etc. What are you planning on working on?įor ignition troubleshooting of antiques with distributors you want an ignition scope, and you want it to be ANALOG. I'm interested in acquiring one for ignition system monitoring, so nothing terribly sophisticated is required.Īn ignition scope and a lab scope are two different things.