 | |
1993 Volvo 850 with 256 kmi Stalled and will not start.
Volvo automobiles Volvo automobiles. (alt.autos.volvo)
 |
| | Thread Tools | Display Modes |
#11
 
| |||
| |||
|
Re: 1993 Volvo 850 with 256 kmi Stalled and will not start. Morefindings -
08-19-2009
, 07:24 PM
| Generally speaking, yes, one wire receives +12V and the other is pulled low by a power transistor in the ECU. The pulse is brief though, especially at start/idle. You really need to connect a test light across the injector connector and crank it, if all is well the light will flash. Sometimes you can also hear the injectors tick but the starter can drown it out. I will be on the hunt for what I think is called a noid light. Thanks! That's the tool designed for the job, but it's not the only way to do it. In a pinch you can take one of those wedge based bulbs used as side markers on a lot of cars, bend down the wire contacts and poke them into the injector connector. Another approach is a regular automotive test light, the sort that looks similar to a screwdriver with a sharp tip and a bulb in the handle. Poke some thin wires into the contact sockets on the injector connector and connect the test light there. |
since I don't see anything wrong with the wiring. I am so grateful for
your input. I will advise.
#12
| |||
| |||
|
|
James Sweet wrote: Generally speaking, yes, one wire receives +12V and the other is pulled low by a power transistor in the ECU. The pulse is brief though, especially at start/idle. You really need to connect a test light across the injector connector and crank it, if all is well the light will flash. Sometimes you can also hear the injectors tick but the starter can drown it out. I will be on the hunt for what I think is called a noid light. Thanks! That's the tool designed for the job, but it's not the only way to do it. In a pinch you can take one of those wedge based bulbs used as side markers on a lot of cars, bend down the wire contacts and poke them into the injector connector. Another approach is a regular automotive test light, the sort that looks similar to a screwdriver with a sharp tip and a bulb in the handle. Poke some thin wires into the contact sockets on the injector connector and connect the test light there. the IAC does buzz. I have ordered a Fuel Injector Main Relay, circa $29, since I don't see anything wrong with the wiring. I am so grateful for your input. I will advise. |
Did you check the output of the injectors? I'm not sure where the relay
is wired in those cars, but normally that just serves to control power
to the whole system, a relay is much too slow to do the actual injector
pulsing. Don't just throw money at it, diagnose.
#13
| |||
| |||
|
#14
| |||
| |||
|
|
Mark Barron wrote: James Sweet wrote: Generally speaking, yes, one wire receives +12V and the other is pulled low by a power transistor in the ECU. The pulse is brief though, especially at start/idle. You really need to connect a test light across the injector connector and crank it, if all is well the light will flash. Sometimes you can also hear the injectors tick but the starter can drown it out. I will be on the hunt for what I think is called a noid light. Thanks! That's the tool designed for the job, but it's not the only way to do it. In a pinch you can take one of those wedge based bulbs used as side markers on a lot of cars, bend down the wire contacts and poke them into the injector connector. Another approach is a regular automotive test light, the sort that looks similar to a screwdriver with a sharp tip and a bulb in the handle. Poke some thin wires into the contact sockets on the injector connector and connect the test light there. the IAC does buzz. I have ordered a Fuel Injector Main Relay, circa $29, since I don't see anything wrong with the wiring. I am so grateful for your input. I will advise. Did you check the output of the injectors? I'm not sure where the relay is wired in those cars, but normally that just serves to control power to the whole system, a relay is much too slow to do the actual injector pulsing. Don't just throw money at it, diagnose. |
injectors to see gasoline
spray right?
I have replaced the distributor cap. I thought the distributor rotor
looked ok.
I tried again to start the 850 with a fully charged battery. A2 and A6
were
totally empty of codes both before and after the try. The car did
turned over
well but did not even cough. Half way through the 20 second crank I
tried some
Starter fluid into the intake. The Air Filter assembly was removed.
and the
MAF sensor disconnected. I was thinking about the possibility that the
FIMainRelay
being good but the wires to the same being bad. Below are the readings
I got.
Fuel Injector Main Relay Connector 4-Female .
Wires going out below page
____________
/ \
Quote:
|
87 30 | | 85 86 | | ---------------- |
87 Thick Green
30 Thick Red
85 Thin Brown
86 Thick Red
With Ignition Off
-----------------
Wire To Grnd Volt To Grnd Ohms
87 0.0 1590
30 12.6 16 Meg
85 0.0 infinite
86 12.6 16 Meg
With Ignition ON
----------------
87 0.0
30 12.6
85 0.0
86 12.6
DVM readings done later with weak battery at 12.6 Volt
#15
| |||
| |||
|
|
On Aug 19, 11:30*pm, James Sweet <jamesrsw... (AT) gmail (DOT) com> wrote: Mark Barron wrote: James Sweet wrote: Generally speaking, yes, one wire receives +12V and the other is pulled low by a power transistor in the ECU. The pulse is brief though, especially at start/idle. You really need to connect a test light across the injector connector and crank it, if all is well the light will flash. Sometimes you can also hear the injectors tick but the starter can drown it out. I will be on the hunt for what I think is called a noid light. Thanks! That's the tool designed for the job, but it's not the only way to do it. In a pinch you can take one of those wedge based bulbs used as side markers on a lot of cars, bend down the wire contacts and poke them into the injector connector. Another approach is a regular automotive test light, the sort that looks similar to a screwdriver with a sharp tip and a bulb in the handle. Poke some thin wires into the contact sockets on the injector connector and connect the test light there. the IAC does buzz. I have ordered a Fuel Injector Main Relay, circa $29, since I don't see anything wrong with the wiring. I am so grateful for your input. I will advise. Did you check the output of the injectors? I'm not sure where the relay is wired in those cars, but normally that just serves to control power to the whole system, a relay is much too slow to do the actual injector pulsing. Don't just throw money at it, diagnose. When you say, 'check output of injectors' you must mean pulling injectors to see gasoline spray right? I have replaced the distributor cap. I thought the distributor rotor looked ok. I tried again to start the 850 with a fully charged battery. A2 and A6 were totally empty of codes both before and after the try. The car did turned over well but did not even cough. Half way through the 20 second crank I tried some Starter fluid into the intake. The Air Filter assembly was removed. and the MAF sensor disconnected. I was thinking about the possibility that the FIMainRelay being good but the wires to the same being bad. Below are the readings I got. Fuel Injector Main Relay Connector 4-Female . Wires going out below page * ____________ */ * * * * * * \ *| 87 * * *30 * | *| * * * * * * *| *| 85 * * *86 * | *| * * * * * * *| *---------------- *87 *Thick Green *30 *Thick Red *85 *Thin Brown *86 *Thick Red *With Ignition Off *----------------- *Wire * * * * * To Grnd Volt * * * * * *To Grnd Ohms *87 * * * * * * * * * * 0.0 * * * * * ** * * * 1590 *30 * * * * * * * * * * 12.6 * * * * * * * * * *16 Meg *85 * * * * * * * * * * 0.0 * * * * * ** * * * infinite *86 * * * * * * * * * * 12.6 * * * * * * * * * *16 Meg *With Ignition ON *---------------- *87 * * * * * * * * * * 0.0 *30 * * * * * * * * * * 12.6 *85 * * * * * * * * * * 0.0 *86 * * * * * * * * * * 12.6 *DVM readings done later with weak battery at 12.6 Volt |
The 1590 ohms at pin 87 did not seem right.
I tested the resistance at pin 87 with the
ignition turned on, it read 2.6 Mega Ohms.
I don't know the specs for the fuel injector
current, but it would be a very tiny current
flowing at 12 V through that kind of resistance
- or am I looking at this wrong?
Where do I find the other end of the wire at pin 87
of the main fuel injector relay?
Thanks for much for reading.
#16
| |||
| |||
|
|
James Sweet wrote: Mark Barron wrote: James Sweet wrote: Mark Barron wrote: The car was driven a couple of miles. It was behaving well but had a fairly rough idle. The car came to a stop, the accelerator was press, the car began to move and then stalled and has not started since. The plugs are new and have good spark The fuel rail has 43 psi. Pressure bleeds away overnight. The pressure reaches 43 psi very quickly. If i crank the engine, the plugs do not appear to be wet. If I stick in a twist of paper towel in the spark plug hole in place of a plug, the towel does not appear to be wet after a 5 second crank. I can however smell gas then. -The resistance of the VSS speed sensor is 1740 ohms instead of the expected 200 ohms. -There is 11 volts between CMP sensor term 3 and ground (10 V is expected) -CMP terminal 1 to ground is 0 ohms, as desired -when I check the power stage control signal (terminal 4 to ground) I get 0.2 volts, where I read I should have 0.7-1.3 V (what does this mean?) I have an 98 S70 to pull parts from. Questions: 1. I have a diagnosis write up(named "BasicTesting-Turbo.pdf" for a Volvo and it says to use a breakout box( I don't have one) for a CMP sensor test, that is "check between BOBox terminal 20 and 4 and Operate the starter voltage should vary between 0-5 volts" Would the terminals 20 and 4 correspond to wires labeled 20 and 4 in a Haynes Volvo 850 wiring diagram? 2. Can a ECU from a 98 s70 go in an 850? Roughly what would I have to pay for an ECU? 3. What do I do next? I wish I had a better write-up. Thanks for reading. Many Thanks, Mark Do you know if you're getting a spark? That's the first thing I'd check, if you have a spark, then the problem is probably fuel, but if you smell gas, I'm leaning towards ignition. I have spark, but even when I squirt starter fluid into the intake directly, I can not get the engine to even cough. How can that be? I will check again to insure that I still have spark. Thanks you for replying. Mark Is there compression? Timing belt didn't break did it? The timing belt did not break. I got the following compression readings 1-4. Battery was too low to get #5. 75 85 98 65 psi |
#17
| |||
| |||
|
|
Hey guys I think I found something. The 1590 ohms at pin 87 did not seem right. I tested the resistance at pin 87 with the ignition turned on, it read 2.6 Mega Ohms. I don't know the specs for the fuel injector current, but it would be a very tiny current flowing at 12 V through that kind of resistance - or am I looking at this wrong? Where do I find the other end of the wire at pin 87 of the main fuel injector relay? Thanks for much for reading. |
That sounds like the relay coil resistance, I don't know the pinout off
hand, but if that's what it is, then that's about right.
With the ignition turned on there is voltage there, so if you try
checking resistance you'll get a meaningless value. In this case it
sounds like your meter is effectively pegged.
|
« Previous Thread
|
Next Thread »
| Thread Tools | |
| Display Modes | |
Linear Mode
| |
Powered by vBulletin
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.