[phireman]

So I had been experiencing a sputter and working on diagnosing that. Now, it just dies on me.

Startup is as usual with no difficulty and nothing sounds amiss, but dies quickly after (within 30 seconds). Plus, if I drop it in gear and press the gas it dies immediately. Check Engine has yet to come on.

Battery is charged. I had already ran sea foam for the fuel injection, replaced spark plugs and a worn distributor rotor (plug wires are next), but nothing about that sputtering had changed. So, I'm leaning towards fuel issue, maybe?

 

[Oldcivicjoe]

The MAP sensor is going to be my first suspect given the progression of the symptoms and how many ive replaced over the last 6 months or so. Grab your multimeter and a vacuum pump and beat it up a bit while testing between 21 and 14 mmHg, vibration and shock sensitivity in that range seems to be the best way to find a bad one quickly.

 

[phireman]

Great! Thanks for your feedback.

Just started diagnosing today and finally got blinks on my OBD 0

It blinks 6 times with 4-5 second pause. What now? Never had a car with OBD 0. Of course I'll start researching, but sounds like you have plenty of experience so I'm open to any help. Thanks again!

Ok, so nevermind that. Pulling my temp sensor triggered that apparently. I reset it. On to the next thing.

 

[Oldcivicjoe]

First things first, test the map sensor, a cheap dvom and a cheap vacuum pump set, about $30 total from harbor freight will get what you need to test. Key on, engine off, map sensor pulled off and back probing the signal wire there should be no voltage drop outs or flat spots where voltage dosent move with different increments of vacuum, like I said they usually present with fluctuations between 21mmhg and 14mmhg from shock/vibration while back probing, sometimes makes it easier to see when the temp is up to operating temp, so a ceramic heater might help, hanging the sensor in front of it about 15 mins.

 

[phireman]

So this is all I have. Will I be able to get the reading you're referring to with this? (I'm not well-versed in it's many uses unfortunately). And as for a vacuum pump, I do have the one included with my brake bleeding kit. Good enough or no?

 

[Oldcivicjoe]

That will do, set to 20 volts DC which is 3 clicks clockwise.

 

[phireman]

I was able to check it out finally. I've included a pic of my setup, let me know if it's correct.
Doing the voltage check with the setting you recommended, the multimeter read around 4.2 (I'm doing this myself so I had to rig the meter's ground where I could while turning the key. Ground in another position and showed around 5, but either way not a lot of fluctuation) That's with the pump set at various levels between 15-20mmhg.

Also, I did end up having to change the coil after checking with the multimeter, but now the motor won't turn over at all.

Thanks for your guidance.

 

[phireman]

FYI the meter was hooked to the yellow wire.
Other readings as follows:
White: around 2
Green: .2ish and dropped to 0 when I turned the key over.

 

[Oldcivicjoe]

I belive its the white wire you should be probing, but id have to look it up, don't need to crank anything when testing, just tap the sensor with a rubber handle driver or ratchet with vacuum applied, make sure it does the full scale from .8 to 4.8 volts with no sudden drop outs or flat spots where the output voltage dosent vary with different amounts of vacuum/ pressure applied. Sounds like you may need to check ground cables from trans bracket to chassis, and chassis to battery as well as charge the battery fully.

 

[phireman]

Ok, so checking the white wire shows a range from .8-2.8 max. Battery is on the charger just in case so ill check again in a while.

 

[Oldcivicjoe]

You will need to blow to get it above 2.8v but it really shouldn't matter as its NA and you won't ever have boost making it go above 2.8. Just kinda smack it around a bit to verify nothing funny going on with vacuum applied.

 

[phireman]

Still had the same result, so the MAP is all good it seems?

Outside that:
Main relay clicks open and shut
Fuel pump kicks in
I replaced the fuel filter (but come to think of it, after replacing and fiddling around some, I loosened the pressure release bolt and there was no pressure relief and the filter was all but empty. Should that tell me something)

 

[Oldcivicjoe]

Pull the inspection plug and cycle the key on and off, fuel should squirt out, if not we may be looking at a dead or nearly dead fuel pump, now would be a great time to go rent a fp test kit 😃

 

[phireman]

So I used your recommended check and no fuel squirted out. I checked the voltage and it's 11+ Already checked the main relay and it's clicking over reliably.

I'm going to borrow or rent a FP check kit. Keepin it movin 😓 You know, before I started really getting into it, I was feeling that the problem was likely fuel delivery. But, my ignition system need a lot of attention, so I'm glad to be taking care of it. Thanks again!

 

[Georgia Eg]

You could also have a bad hose that connects from pump to outlet, but if you have voltage, and nothing coming out, and you're not pulling the return line instead of the pressure side then either hose, completely clogged strainer, or bad pump.

 

[phireman]

Pull the inspection plug and cycle the key on and off, fuel should squirt out, if not we may be looking at a dead or nearly dead fuel pump, now would be a great time to go rent a fp test kit 😃

So I ran the test and to my surprise I got pressure, 38psi consistently with 3 attempts. Still no start. Does this rule out my pump? So, where to go from here? Fuel injection?

 

[Georgia Eg]

38 psi @ the rail?

 

[phireman]

At the fuel filter. I didn't check at the rail, but this is still DPFI, so does that apply? Or is there something I'm not following?

 

[Oldcivicjoe]

It could be a stuck regulator that isn't allowing the air to purge, but it should have when you pulled the plug and turned the key, does it fire at all with the gauge hooked up?

 

[drtalon123]

Does it/can it run on an external fuel source?

Give the TB a shot of flammable brake clean or TB cleaner, and try starting it.

If it cranks up but dies after a shot of something flammable, you know the engine can run and has good spark/compression/timing.

If it doesnt run with the shot, your problem may not be fuel related at all.