[SOLVED] fluctuating hpfp psi, p0202, afr 29 on throttle

From the pictures you've shared, it's apparent that the car was not treated well by the prior owner. Any number of things could be a problem waiting for an excuse to appear.
 
chris' speed 3 said:
im going to take a look at that, what I don’t understand is the car was working fine for the last 3 weeks since I did the maintenance on my injectors so why is it all of a sudden the plug would be faulty?
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Vibration, heat add to that pins not seated properly or bent/damaged. It has happened here before. With proper diagnosis the problem was found pretty easily.
<<read here>> ...might be of some value
@L337TurboZ has a thread on electrical diagnosis <<here>> ...very valuable car life skills
 
SyntheticAtmosphere said:
Vibration, heat add to that pins not seated properly or bent/damaged. It has happened here before. With proper diagnosis the problem was found pretty easily.
<<read here>> ...might be of some value
@L337TurboZ has a thread on electrical diagnosis <<here>> ...very valuable car life skills
Click to expand...

Thank you this is super helpful, I'm going to read through both threads, I checked through the wiring harness for the injectors all the way up too the ECU and none of the pins in the connectors looked damaged.

The first night this issue came up there was a fuse that popped out, one of the purple 40's on the top left and I pushed it back in and the car ran as its supped to after that until tuesday. I checked out my fuses as well and they all looked good besides some calcium buildup. Do you think its possible one of the fuses is damaged but not visibly? (like the connection being burnt). Also the big blue fuse (def inj) in the top left was really warm I don't know if that has any significance. @SyntheticAtmosphere
 
If you have a multimeter you can check the fuses for continuity.
 
Fuses pop due to two possible reasons. First is a direct short to ground (most likely as all fuses on 99 percent of cars are on the positive side) and two a spike in amperage.

You probably have a short in the harness or an injector that is shorting out internally.
 
L337TurboZ said:
Fuses pop due to two possible reasons. First is a direct short to ground (most likely as all fuses on 99 percent of cars are on the positive side) and two a spike in amperage.

You probably have a short in the harness or an injector that is shorting out internally.
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I tested cylinder 2 injector resistance i believe, setting the multimeter to ohms and got 1.1 and i checked #3 to compare and it was also 1.1 so does that rule out the injectors?

What would cause a short to ground?

Thanks
 
Did you test it directly at the pins on the injector or through the harness? You also need to check each pin on the injector to the injector body (the outer casing of the injector) if you have any reading between a pin and the body of the injector then it is shorted.

A short to ground is usually a broken wire or a rubbed wire where it's contacting bare metal.

A fuse won't pop due to high resistance. It will get hot if the circuit is pushing amperage close to it's limits. For example if it's a 20 amp fuse and you're right around 18 amps it's gonna strain the fuse/circuit. Fuses are made for spikes in amperage. Fusable links are made to slow burn. Cars don't really use fusable links anymore and the Speed 3 doesn't haven't any of those so don't worry about that. Just focus on isolating any wiring issue that can cause a fuse to pop.
 
L337TurboZ said:
Did you test it directly at the pins on the injector or through the harness? You also need to check each pin on the injector to the injector body (the outer casing of the injector) if you have any reading between a pin and the body of the injector then it is shorted.

A short to ground is usually a broken wire or a rubbed wire where it's contacting bare metal.

A fuse won't pop due to high resistance. It will get hot if the circuit is pushing amperage close to it's limits. For example if it's a 20 amp fuse and you're right around 18 amps it's gonna strain the fuse/circuit. Fuses are made for spikes in amperage. Fusable links are made to slow burn. Cars don't really use fusable links anymore and the Speed 3 doesn't haven't any of those so don't worry about that. Just focus on isolating any wiring issue that can cause a fuse to pop.
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i checked it at the pins coming out of the injector where the connector plugs into. One lead on each pin, however im reading your thread on electronic 101 and trying to learn more about this. When you say check each pin do you mean put one lead on the pin and put the other on the metal part of the injector on the top, isn't the outer casing made of plastic? to perform this test my multimeter should be set to ohms right?
thank you
 
The casing on the injector isn't plastic it's metal. The part that is plastic is to keep the pins separate from each other. You can test each pin and check for continuity to the cylinder head or ground. You shouldn't have any resistance reading between each pin and ground.

Then you need to check both pins at the injector and measure the resistance of the field coil inside the injector. I don't know what the specification for the injectors are but look it up and compare what you're reading with the meter to what spec is.
 
L337TurboZ said:
The casing on the injector isn't plastic it's metal. The part that is plastic is to keep the pins separate from each other. You can test each pin and check for continuity to the cylinder head or ground. You shouldn't have any resistance reading between each pin and ground.

Then you need to check both pins at the injector and measure the resistance of the field coil inside the injector. I don't know what the specification for the injectors are but look it up and compare what you're reading with the meter to what spec is.
Click to expand...
The resistance on the coil was 1-1.1 same throughout my injectors and also what someone else on another thread was getting.
 
So tonights diagnoses @L337TurboZ @Enki @SyntheticAtmosphere I appreciate everyone’s help

my fuel injector read continuity between the two pins and when putting one lead on the injector pin and one on the cylinder head or ground terminal there’s no reading, so that’s good

now for testing the harness I started with the main injector harness I get a reading for continuity from the injectors connector to the connector that plugs into the main harness(picture below), so that’s good

Next I tested the following part of the harness with my dad from one connector to the next and once again there was continuity(picture of connectors attached)

So I put my battery in with everything else is missing just to test wiring, I set my multimeter to the voltage with the straight line. I got 3 ish volts at all 4 injector connectors so that makes me think that it’s the connection between the injector itself and the harness that’s causing my problem.
There was a loud humming noise and ticking noise as well, but not all hoses and connectors were connected. Could be the fuel pump trying to prime but the fuel lines are open. I’m just throwing this in here incase it’s relevant.

i also read somewhere abt the clicking for the computers all shutting down after turning the key on/off and I hear 3-4 clicks so no issues with that I suppose

if there’s anything else you guys think I should look at let me know, or is it time to bolt the car back up and make sure everything is connected properly?
 

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