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1986 740 turbo crank no start issue

Fuel is now making it to the rail, injectors are getting power but the car won't stay running. Insufficient fuel pressure?
 
Get a gauge on there and check. How would WE know?

Do an idle test and a snap throttle test.

What do you mean fuel is "making it to the rail"?

There is fuel pressure and also volume. Maybe one of your new pumps has gone bad.

Maybe retry the fuel injector spray into a bottle thing again.
 
dfk said:
1986 740, B230FT LH 2.2 Crank no start issue.

Car cranks over with no sputtering or attempts to start up at all. Car will start and run if fluid is sprayed in TB until you stop spraying.
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There is no fuel.

ZVOLV said:
Since it runs on fluid it's likely a fuel issue.
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Now, there is a pump in the tank and a main pump under the car. Both are controlled by the Fuel Pump Relay.

What is the voltage at the main pump *before* attempting to start.
What is the voltage at the main pump *while* attempting to start.

What is the voltage at the in-tank pump *before* attempting to start.
What is the voltage at the in-tank pump *while* attempting to start.

Have you disconnected the fuel line going *into* the main pump (coming from the back of the car) and verified that there is a lot of fuel coming out of the tank while attempting to crank the car (would likely overfill a 16oz bottle while cranking for three or four seconds)?

ZVOLV said:
What do you mean fuel is "making it to the rail"?
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I would also like to know...

Does breaking the connector at the rail (male/female 14mm connections IIRC) cause there to be enough fuel that it is literally sprayed from the connector when you break it?
 
Just so you know...

The only way you would have a fuel pressure problem that would present a no-start condition and NOT have a dead pump is for the fuel to be dumping all over the ground...

AFAIK, even a bad fuel pressure regulator would allow the car to crank and idle (albeit roughly...) But, this is the reason why ZVOLV has been trying to get you to pull the return line.
 
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Okay, got the car to fire up by unplugging the maf, started idling at around 1300rpm, stayed there as it reached operating temperature. The car wasn't responsive to rapid throttle actions like if you tried to blip the throttle it wouldn't accellerate, if you gave a slow steady increase in throttle it will rev up but drops to about 800 rpm upon throttle release. Shut the car off and it wouldn't start back up again, I suspect a faulty CTS. Would that cause my other issues as well?
 
dfk said:
Okay, got the car to fire up by unplugging the maf, started idling at around 1300rpm, stayed there as it reached operating temperature. The car wasn't responsive to rapid throttle actions like if you tried to blip the throttle it wouldn't accellerate, if you gave a slow steady increase in throttle it will rev up but drops to about 800 rpm upon throttle release. Shut the car off and it wouldn't start back up again, I suspect a faulty CTS. Would that cause my other issues as well?
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All these issues were with maf plugged in, tried starting the car with maf unplugged and plugged in made no difference
 
ZVOLV said:
Sounds like intermittent electrical. Not enough info here to diag. Good luck.
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Darn shame, thanks for all the help you've given thus far.

Anyone else care to diagnose? Pressure is verified at the rail and I'm getting
spark
 
Current symptoms are as follow:

Car will not stay running while MAF is plugged in if you crank for approx. 6-8 seconds with the throttle fully open it will sputter to life for about 4 seconds and then slowly die back down.
Car will start with the MAF unplugged if you crank for approx. 6-8 seconds with the throttle fully open it will slowly increase rpm's enough and idle in a limp mode of sorts. From here, the car can be manipulated to idle by manually holding the throttle at 20% for 15-20 seconds. After some time, the MAF can be plugged in and the car will idle quite smoothly at 1300-1400 RPM, but acts quite bizarre. If you try to smoothly engage the throttle it will increase in RPM without hitch, however, if you try to 'blip' (going from fully closed to about 60-75% open quite quickly) the throttle, the car will not respond and if you attempt to 'blip' it repeatedly it will start to stall out.

Things I've confirmed

Spark is present
Firing order is correct
Repaired engine bay wiring harness
Cam is in time with crank
FPR is not ruptured, though you can smell the very faint smell of gas at the vacuum line although the line is clear of gas
Both pumps are running

Thanks again for trying to diagnose over the computer, I understand this is very difficult to do.
 
dfk said:
FPR is not ruptured, though you can smell the very faint smell of gas at the vacuum line although the line is clear of gas
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It's not difficult to diagnose a no start over the internet - I used to do it every other night on the telephone long distance - driveabilties too - difference was, those people listened

You need FUEL - FIRE - COMPRESSION

If you have all 3 of those at the right place and the right time your car will run

You eliminated two of those as the cause for the "no start" in your first post when you stated that the car WOULD RUN if you provided FUEL

So, what does that tell you? Where would you think the problem is?

Also, still waiting to hear back from you on if you have CONFIRMED INJECTOR PULSE

NO STARTS ARE NOT DIFFICULT TO NAIL DOWN - I'll take a "no start" over an intermittent issue any day of the week

There is no need in people giving you good advice if you are either going to just ignore it or already have it in your mind to do other things

STOP GUESSING and asking random "could this be it" questions and follow up on the suggestions you have been given - follow a logical process of elimination (by actually checking and testing) - you'll find the cause if you do

The deal with the MAF was pure coincidence and NO, A CTS IS NOT going to be causing you this

On a side note, whether it's the direct cause or just a contributing factor, or not, if you can smell fuel out of the vacuum line for the CPR then you need to replace the CPR

It is bad
 
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Problem has been found, turned out I had the CTS plugged into the knock sensor and vice versa, silly mistake.
 
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