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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #1
just as it says i have confirmed my fuel injectors are spraying so what do I check now?

thanks in advance
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #2
i would think it would have something to do with the spark not happening but i dont know
 

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Outstanding Contributor
450slc5.0cab 280sl5sp 280se4.5 500se+500slAMG +250seStkW108 350sl4spdX3 500secEuro
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But it runs with a spray of something combustible in the intake, right?

That would tell me you have spark.

Air is easy to get usually.

So there must be more tithe story.
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #4
But it runs with a spray of something combustible in the intake, right?

That would tell me you have spark.

Air is easy to get usually.

So there must be more tithe story.
it is like one cylinder fires each time around or one or two seems very random
 

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Premium Member
1975 450SL
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2,440 Posts
You may be getting spark, but are you getting the spark at the right time and place? Your timing could be off, or your dwell could be off.

I had a lot of trouble on my D-Jet (same as yours) ignition with the points. The points under the distributor cap need to open and close for a specific amount of time at just the right time for best results. Breaker points type ignitions are an older technology, so they aren't thought of by many mechanics.

Make sure the timing is set right. There have been many stories of people getting the plug wires one post off at the distributor, or getting the dizzy itself one gear tooth off when replacing it. Just something to look for. There have even been reports of not getting the cap or rotor seated correctly.

Check to make sure the wiring is good, there is a green wire from the dizzy to a switch module behind the driver side headlights that has been known to have insulation crack off, the conductors break, and the terminal go bad. It's exposed to a lot of heat over time.

Just a few wild guesses over the internet, good luck,
Scott
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #6
Thanks for the input and wild guesses are better than nothing and I'll post a video later

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Premium Member
'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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10,340 Posts
You may be getting spark, but are you getting the spark at the right time and place? Your timing could be off, or your dwell could be off.

I had a lot of trouble on my D-Jet (same as yours) ignition with the points. The points under the distributor cap need to open and close for a specific amount of time at just the right time for best results. Breaker points type ignitions are an older technology, so they aren't thought of by many mechanics.

Make sure the timing is set right. There have been many stories of people getting the plug wires one post off at the distributor, or getting the dizzy itself one gear tooth off when replacing it. Just something to look for. There have even been reports of not getting the cap or rotor seated correctly.

Check to make sure the wiring is good, there is a green wire from the dizzy to a switch module behind the driver side headlights that has been known to have insulation crack off, the conductors break, and the terminal go bad. It's exposed to a lot of heat over time.

Scott
All good points (no pun intended). Some of my early experiences with similar symptoms:

- The green wire from distributor goes to one side of one of the resistors on the 72. I had mine short out against exhaust manifold when insulation melted.
Check that it is connected in distributor and is good all way to terminal at resistor.
- Wires installed incorrectly. I did that once - one side was right, but I reversed order on other side :eek:. I then parked distributor cap with proper numbers as well as wires. Made sure I knew the correct order number of the plugs and reattached wires. Engine ran a lot better ;)
- The rotor should be pointing toward a mark on the distributor when engine is at TDC (on flywheel and with passenger side cams pointin up like rabbits ears (as seen through oil filler cap)
- For timing to be correct, distributor hold down bolt should be near end of adjustment slot when you turn distributor CCW.
- Set points at 0.014" when rubbing block is at top of distr cam. (dwell should be about right withe this setting). Move rotor back & forth and make sure points open and close)
- check that distributor cap has no cracks, clean contact points for rotor. Then make sure it seats fully.
- check that wires are fully inserted into distributor and that plug end fits firmly onto top threaded section of plugs.
- spin engine over and check if you have a spark. ( can be hardardous if gas is leaking - mayber buy one of the HF gizmos for checking spark? Maybe others can advise on how they do this)

Don't ask - I have learned this stuff the hard way.

I suppose there is always the possibility of bad coil or bad switchgear. A Pertronix upgrade would be a way of eleiminating those and the points.
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #8
alright so i took a video, im just waiting for that to upload MBGraham you lost me after simple wire checking which i just did. also is there an electronic ignition upgrade or something of that nature, might have been what mb was saying but im not sure
 

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'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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MBGraham you lost me after simple wire checking which i just did. also
You should read through the thread that Proctologist assembled in EG (stickies) in D-Jet section. Perhaps the pics will help in understanding what we are talking about.

I can't be sure, but it doesn't sound like car is getting enough gas. What happens if you spray starter fluid in while you are cranking - can you keep it running? Maybe the cold start valve/injector is not working? How about fuel pressure - is it 2bar ~30psig) ? You have to learn how to check these.

But if not a fuel problem, you should check that plugs are sparking.
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #12
What voltage should be running to my injectors?

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R/C107 Moderator
1986 560SL: '84 500SL: '84 280SL 5 speed: other 107s
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32,362 Posts
Check the connector on the ECU. Check the ECU relay. Check fuses. OE fuses tend to have corroded contacts so they need to be removed and the contacts cleaned.
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #14
Ok thanks I'll check those, this car ran and then was just stopped and was not started, so nothing was tampered with from the running form

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450slc5.0cab 280sl5sp 280se4.5 500se+500slAMG +250seStkW108 350sl4spdX3 500secEuro
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I agree that it sounds like it is not getting fuel. If it is getting fuel, then your exhaust should smell like a gas station pump after that much cranking.

Please take a video of dumping/spraying something combustible in the throttle body and doing the same cranking.

Good video. You will get there with the forum's help.
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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Discussion Starter #16
It seems that my injectors aren't getting any power

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R/C107 Moderator
1986 560SL: '84 500SL: '84 280SL 5 speed: other 107s
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32,362 Posts
And the ECU is the main component that controls the injectors. It receives information from sensors and the trigger points. The fact that is was stored for several years leads me to think there may be corroded contacts. Also check for damaged wiring. Mice wreak havoc in a very short time.
 

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1972 450sl 10704412002908 and 2005 toyota tacoma
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89 Posts
Discussion Starter #18
I was pulling out the main relay #3 and at the same time all the wires fell out of the back, so if anyone knows how that would go back I would really appreciate that

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