Distributors and Trigger Points (New Dizzy Installed), Troubleshooting Parts - CHT appears bad |
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Distributors and Trigger Points (New Dizzy Installed), Troubleshooting Parts - CHT appears bad |
tvdinnerbythepool |
Sep 9 2021, 08:43 AM
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#1
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Member Group: Members Posts: 310 Joined: 24-July 18 From: Olympia, WA Member No.: 22,336 Region Association: Pacific Northwest |
Hey all,
I am still chasing down an intermittent RICH condition when the car is fully warmed up. 1.7L D-Jet After fully warmed up with a tuned and rebuilt MPS I can come to a stop light and idle steady at 850rpms, next stop light it's bogging down to almost 200-300 and barely running. Then next light it's idling normally again. Some days I have no issues with idle at all, others I do. I've gone through all the components and troubleshot my way through everything on the PBANDERS list of "my car is running rich". I am as confident as I can be through extensive troubleshooting and testing that my ECU, AAR, MPS, CSV, Vacuum Leaks, CHT, Injectors, Fuel Pressure etc are all good. All new wiring harnesses, plugs, plug wires, cap, rotor, coil, etc. The ONLY thing I haven't worked on is the distributor. I am reading up on the possibility of the Trigger Sensor Contacts being warn and bouncing possibly shooting off extra injection pulses...could this be the cause of the intermittent problem? It doesn't have points anymore, but a petronix I believe. What do you guys think? Is there an easy test for this or do I replace the trigger contacts or the whole dizzy? Cheers! (IMG:style_emoticons/default/beerchug.gif) |
emerygt350 |
Sep 26 2021, 05:21 AM
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#2
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Advanced Member Group: Members Posts: 2,096 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Hmmm, I read that the original design set the injectors up in two banks. There are 4 cylinders and only two triggers. One cylinder would get it right before the intake stroke, the other fires as well but the charge just has to wait in the manifold till the intake opens.
"An additional input is required so that the ECU will synchronize the fuel injectors with the piston strokes. It therefore receives signals from a set of dual Trigger Points in the base of the ignition distributor. Each of the two points controls two injectors (in our four-cylinder motors, anyway)" "Note that output to Injectors at pins 3, 4, and 5, 6 run through 6Ohm 5Watt Resistors. These serve to limit the current applied to Injectors (See also: Dropping Resistors) and effectively drop the voltage actually applied Injectors to 3V. They are then tied together internally to the transistor switches, therefore, Injectors fire in pairs! 1, 3 together, and 2, 4 together." https://www.sw-em.com/bosch_d-jetronic_injection.htm And other sources (Chilton's) |
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