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yarin
Does anyone know what the specs are for the injector resistor pack on a 2.0?

Impedence, wattage?

Thanks. To those who built their own resistor packs for a custom fuel injection application using stock 2.0 injectors what parts did you use?

Thanks
Mark Henry
About 3 ohms
lapuwali
They're 3-5 ohms, typically. An injector is going to sink 2-3A, so figure on 35-40W (i.e., really big-assed ceramic resistors). I've usually seen a heatsink used.
sean_v8_914
2.0 D-Jet resistor pack? where is that? I have only seen the resistor pack on 1.8 L-jet
JFJ914
QUOTE(sean_v8_914 @ May 18 2006, 05:12 PM) *

2.0 D-Jet resistor pack? where is that? I have only seen the resistor pack on 1.8 L-jet



It's inside the ECU for all D Jet.
lapuwali
This is for Megasquirt. He's using 2.0 injectors (low-impedance) and was using the MS PWM feature, but now suspects it's causing problems, so he's moving to a resistor pack instead.

L-Jet runs an external resistor pack. D-Jet appears to do current limiting in the ECU, but it may not be via bulk resistors.

mightyohm
The resistors inside the ECU are about 6 ohms and look like 10-30W, heatsunk to the case.

In my MS install I used 8 ohm 25W aluminum body resistors because I found them cheap at my local surplus electronics store.
I don't think the exact value is super critical as long as it's 5-10 ohms.
yarin
Thanks guys.. i'll see what i can find.

It's tough trying to get this project going without knowing if my injectors are good or not. I had them cleaned and checked, but turns out one was stuck closed and one stuck open. Who knows about the rest. I found 4 more 2.0 injectors, untested though.

I'm looking for 4 known good 1.7L injectors. Anyone got any to sell?
lapuwali
Doesn't speak well for the injector clean/test services when you use them and they send back injectors that still don't work.

I have a set of 2.0 injectors in unknown condition (never tried them, they came with a pile of parts). If you can't assemble a usable set from the 8 you have, I'd be willing to sell you these. Perhaps you need to try a different injector service. Did you use RC or someone else?
yarin
QUOTE(lapuwali @ May 18 2006, 07:05 PM) *

Doesn't speak well for the injector clean/test services when you use them and they send back injectors that still don't work.

I have a set of 2.0 injectors in unknown condition (never tried them, they came with a pile of parts). If you can't assemble a usable set from the 8 you have, I'd be willing to sell you these. Perhaps you need to try a different injector service. Did you use RC or someone else?


There is a chance the injector driver might have damaged them. I did drive the car a bit and idle for at least 1/2 hr with 2 injectors on the bad channel. They might have been overheated, who knows. I'll send them back for testing. I still trust the service, i just dont trust my setup. Thanks for the offer, i'll let you know what happens.
crash914
Yarin,

I used i think 10 ohm resistors about 10 watt. Looks like ballast resistors.

mounted them on the other half of the lid I had for my relay box.
I don't think that it is too critical...
yarin
i'm not going to jump to any conclusions until I can get the thing idling properly... BUT after some rework on the main board and initial testing it looks like I solved the injector driver issue. I replaced one of the 3904 transistors on the PWM active flyback section because an impedence check didn't match from ch1 to ch2. There might have been a bad solder joint, bridge, or flux residue.

I started the car up and tried disconnecting one injector at a time. all caused rpm to drop as expected.

i'm going to hold off on injector resistors for now. but just incase i do have two 15ohm 50watt resistors that i can put in parallel and use for all 4 injectors.

i'm going to vegas for a week so i'm going to try freshly cleaned and tested injectors and new plugs when i get back and see where i am at. right now i dont have a consistent idle or AFR. also the timing light doesnt fire consistently, i believe on one or two plugs.

i'm getting closer.....
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