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2G Random loss in vacuum

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Littlefoot03

Probationary Member
26
0
Sep 17, 2014
island lake, Illinois
So yesterday I was hooking up my oil temp gauge and when I was I'll done I started my car and the idle was super rough. I turned the car off and started it and it just died. My wires are brand new and I can't seem to find any vacuum leaks. Any help would be appreciated!
 
Also at one point while I had the car running it sounded like a spark was arking around somewhere in the engine bay
 
When you say you couldn't find any vacuum leaks, do you mean you performed a boost leak test and received negative results?

If not, do a BLT.

And while you're at it test all the plugs for spark. You could have lost ignition on one or more of your cylinders, which would explain a crappy idle and low vacuum.
 
When you say you couldn't find any vacuum leaks, do you mean you performed a boost leak test and received negative results?

And while you're at it test all the plugs for spark. You could have lost ignition on one or more of your cylinders, which would explain a crappy idle and low vacuum.
I didn't do a blt. But I spayed the vacuum lines with brake cleaner to see if the idle would speed up and nothing happened. I am getting spark on all cylinders. Checked that first
 
Do a BLT and double check your timing marks.
If it holds pressure on a BLT, your timing marks line up and you have good spark, I'd look next to doing a compression test.
 
Do a BLT and double check your timing marks.
If it holds pressure on a BLT, your timing marks line up and you have good spark, I'd look next to doing a compression test.
Okay I'll try those thanks for the help. I'll post my results
 
Do a BLT and double check your timing marks.
Okay so I checked all of that stuff and only found that I had a boost leak that I fixed and it didn't fix the problem. Could it possibly be that my fuel pump is taking a shit on me?
 
You checked spark on all 4? And did a compression test?

I'm assuming since you don't have a vehicle profile filled out that your car is completely stock.

You can try replacing your fuel filter and check your voltage at the pump with the car running. Also, double check to make sure your charging system is working. If your battery / alternator are shot you might not have enough voltage for your coils to create sufficient spark or the pump to create sufficient fuel pressure. (It can really do some weird stuff.)

You are limited to what has been mentioned. There really isn't anything else that could cause the issue you're having short of a toasted ECU or junk injector, and that's a stretch.
 
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I'm new to this website that's why I don't have a vehicle profile but my car is not stock. The only upgrade I could see is the 550cc injector kind of a cheap brand. I will check my voltage at the pump and see where that leads. The charging system is working fine my battery is only like 6 months old and it reads 13.7 volts while running. Could it be the power transistor I looked up that. I didn't think it could be because someone said the tac would read half the real number and mines not
 
You said the plugs are new, was it running fine before the new plugs? Is their a tuning device for the injector?
The plug are new but I have had them for a couple months and the problem just started. And yes an apexi safc. Nothing like ecmlink yet
 
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So I figure it is tuned and was ok before. The transistor is cheep and causes issues like yours, I wound try that next. Im sure their is a how to test thread on here somewhere. No more boost leaks? I no you found and fixed one.
 
So I figure it is tuned and was ok before. The transistor is cheep and causes issues like yours, I wound try that next. Im sure their is a how to test thread on here somewhere. No more boost leaks? I no you found and fixed one.
Yes it was tuned and running good then all of a sudden I started it and it was missing really bad and my vacuum was sitting a - 9 which it is usually at - 17. And thru the last couple of days it's been getting a little worst
 
Here is a video of the noise
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Here is a video of the noise
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That doesn't sound too good man! Did the noise start when you replaced the wires? If so, try putting the old ones back may be you have defective new wires. New things do fail, sometimes. Its rare on wires but it does happen. Good luck to you man. I hope you can figure this one out.
 
That doesn't sound too good man! Did the noise start when you replaced the wires? If so, try putting the old ones back may be you have defective new wires. New things do fail, sometimes. Its rare on wires but it does happen. Good luck to you man. I hope you can figure this one out.
the wires arent brand new but they are less then 6 months old. i cant try the old wires because they broke while taking them off the old owner didnt take care of this car to well
 
How did you check the valve timing? If you trusted the mark on the harmonic balancer lining up with the pointer on the cover, that isn't always right. You need to drop a straw in cyl#1 and confirm TDC by rotating the crank.
 
I thought I saw arching, but after looking at it full screen maybe not. Is the noise coming from the PCV valve? I get a bunch of clicking from mine sometimes because my cams give me a funky idle.
i honestly have no idea where the noise is coming from. ive been trying to use a stethoscope to pin point it but am having no luck. tonight i will start the car in the dark and see if i can see a spark arching but i havent been able to see on in the day time
 
How did you check the valve timing? If you trusted the mark on the harmonic balancer lining up with the pointer on the cover, that isn't always right. You need to drop a straw in cyl#1 and confirm TDC by rotating the crank.
ill check that too now. i recently redid the timing a couple months ago so i figuered the marks would still be lined up
 
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