1990 740 gle gas delivery problem?

joedrt77 · Post by **joedrt77** » 24 Oct 2016, 16:06

New coil, new power stage, new fuel pump relay, still no 12 v. to fuel injectors and no start.

lummert · Post by **lummert** » 24 Oct 2016, 17:57

Have you already checked the radio suppression relay and it's wiring connection? This is what supplies 12 volts to the injectors.

joedrt77 · Post by **joedrt77** » 26 Oct 2016, 15:49

have 2 side by side, swapped them, they both click, jumpered the connection, that is the two thick wires, still no 12 v. at injector connector. Thinking that means no signal from fuel injection module, not sure how to test it with multimeter or my regular non-led test light, don't want to blow anything on the module, can not find a whole test procedure or tutorial.

joedrt77 · Post by **joedrt77** » 26 Oct 2016, 16:01

I have an 02 fault but It doesn't seem like that would keep it from starting, not sure tho?

joedrt77 · Post by **joedrt77** » 26 Oct 2016, 16:16

( I jumpered the rsr relay then tested for 12 volt again at fuel inj. connector still no steady 12 volts, on one side I get like 3.5 volts then goes to 0 quickly, then when i take off the test lead and touch it back to same point on f inj. connector it reads 0 not 3.5 just 0, other side is 0, but as i understand one side will be 0), was at one point getting that BUT now there is no voltage reading at all at the f i connectors.

joedrt77 · Post by **joedrt77** » 28 Oct 2016, 06:11

the coil I'm using has 1.8 on the primary resistance, according to the volvo specs. the coil primary resistance should be .6 to .9, my spark is orange, not using spark tester just using spark plug for testing spark, being 1.8 instead of .6 to .9 is that a problem or is it within tolerance? thanks.

lummert · Post by **lummert** » 28 Oct 2016, 08:20

http://www.volvoclub.org.uk/faq/Electri ... andTesting

joedrt77 · Post by **joedrt77** » 30 Oct 2016, 11:52

Was trying to follow a test procedure, hooked up test light to 3 on rsr relay connector, it lit up as expected, then on the other big wire on same connector, it says it's supposed to blink while engine is cranking but no blink and no light up at all.

joedrt77 · Post by **joedrt77** » 30 Oct 2016, 19:42

Thanks for the help, put those new parts on, cleaned and fiddled with the rsr and got it running again, might still be something intermittent going on but at least it will start, was quite a puzzle.

joedrt77 · Post by **joedrt77** » 30 Oct 2016, 20:00

Thanks again Lummert and regina 93, you guys were right on the money, great advice.