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For the last couple weeks I've been having P0301 cylinder 1 misfire alongside P1237 manufacture defined which was something to do with fuel injector 1. So from those I knew it was the fuel injector. When I came to a stop the engine would start misfiring at cyl 1, but would start firing normally once I put the gas on. It also started surging when under any type of acceleration. I replaced the coil packs and spark plugs (NGK .28 gap platinum) about 2 weeks ago because on of my coil packs died. kept troubleshooting and was able to replicate the misfiring while under the hood with the engine running from fiddling with the plugs that go to the injectors. I've been driving a lot in the city recently and I think all the bumpy roads were slowly dislodging the plugs since they dont lock down.

After pressing all the injector plugs down, I know longer have any surging or cylinder misfires. So now im just wondering where I can get some new plugs to splice in as these will just surely get dislodged again when I'm driving in the city again. Also, oddly enough, I think u was getting more boost when the plugs were loose. Maybe the ECU was compensating somehow, but very randomly the computer would comply with my foot all the way down on the pedal and give me 18psi boost. Now, with the plugs snuggled in tight, it feels more like 12psi, haven't looked yet. I'm hearing that flutter though when you quickly release the gas. Bad diverter valve? Where can I buy an aftermarket diverter? Also where can I get electrical parts? Specifically, for wiring, where you push the connector on and the plastic housing locks on. Most of my plastic housing for the connectors are broken and don't lock on: diverter valve, knock sensor, all 4 coil packs, probably more.

Also, how do you know when you need a new battery? It charges up to 14v and goes down to 12v pretty fast if I'm just sitting in there with the stereo on. Also I can make my engine skip a beat when I roll the window up on an already rolled up window. And the headlights visibly dim at the same time too. What's up with that?

Also, the back seat floor is wet. I thought I fixed that a long time ago because I did clear the holes of debris that's under the battery, but when it started raining again I noticed the problem wasn't fixed. Now I'm fairly certain all the foam underneath will be moldy and I dont know what electricals may be interfered with down there.

Also, when my car is jacked up on the driver side front wheel, I can jiggle the wheel back and forth. It's the upper left joint I think, so I bought two new ones and the tool to pry it off. I just dont know the procedure, I'll try to look it up. But it's pretty bad. I have to hold my steering wheel at 11 o clock to go straight.

Also, hard shifting. Most frequently when coming to a stop and it shifts from 2nd to 1st. Don't say tranny don't say tranny. It used to fairly rarely shake the whole car when shifting from 4th to 5th, but hasn't happened for a while, which makes me think its vacuum related. I really need to replace all those check valves.

Also, I've checked on my pancake valve, or pressure regulating valve, and its been drippy with light brown liquid. It's not thick, it's not watery though either. But is it normal for the PCV system to be more that moist?? Its literally dripping fluid into the larger tube from the pancake valve.

Sigh... not even the half of it. Runs pretty great though. Anyone in Washington that can help me?
 

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Thats a lot of issues for "bad or loose wiring at connectors", kind of confusing to get help on all these in one post. Focus on one main thing on a post or a related issue for better response.

First question to always answer, any codes? VAGCom scan will give you codes that dont trigger CEL's. I assume with misfires you were getting the blinking CEL?

For the injector wirings, check the grounds first, common cause of most any electrical issue. Not totally sure where the ground is for the injectors but worth a look. Check the wires themselves along the rail, if any of the insulation is missing that could be where you issue is, lots of heat and wires get brittle. If you're set on swapping them, there are aftermarket of course but if you have pick & pulls/junk yards, grab a set of off a junked Passat and just splice them in.

The battery issue. What is the voltage with car off? Should be about 12.6, lower than that car can still start but start having issues, good rule of thumb is every .2 volts you lose 25% power of the battery so at 12.4 (75%), 12.2 (50%), 12.0 (25%), you probably won't be able to start.. What is the voltage immediately after start up, it should go down as you just used the battery to do the cranking. Lastly, what is the voltage with the car running? Should be 13.4-14ish, then alternator is working and battery is charging, if it shoots up to 14v but drops to 12v or so, could be alternator but probably a new belt if you haven't changed it in years. Slight dimming of lights isn't out of the ordinary when using accessories.
The DIY section has plenty of information on the wet carpets and the control arm replacements, its not hard, the pinch bolt is the hardest, most irritating part. Again, split the issues into different posts.
 

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Regarding the injector wiring:

You won't find any grounds on the injector wiring. The injectors have a common +12V connection, supplied from a fuse. The ground side of each injector is switched by the ECM, which pulls (connects) it to ground to fire the injector.

This arrangement is used for virtually everything controlled by the ECM. The reason for this design is to better protect the ECM (which is pretty bulletproof). If a short to ground occurs on an ECM output (e.g. an injector control), no harm will come to the ECM, since it was just going to ground the wire anyway. The injector will be stuck on, and might be damaged, but it's easy and inexpensive to repair as compared to the ECM. Further, the ECM has monitoring circuitry that will set an "open circuit or short to ground" code for that output.

Regarding connector repair parts: your VW dealer on a good online retailer like ECS Tuning can provide the exact replacement parts. The connector shells probably have a VW part number on them, so they'd be easy to find. The part numbers are 9 or 10 characters, e.g. 1J0 973 702. You can also buy "repair wires" which are short lengths of yellow wire with the various terminals crimped on the end. You cut the wire in two and splice the ends to your harness. This will get you a good start: https://www.ecstuning.com/Volkswagen-Passat_B5-FWD-1.8T/General_Purpose/Electrical/Connectors/
 

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For the last couple weeks I've been having P0301 cylinder 1 misfire alongside P1237 manufacture defined which was something to do with fuel injector 1. So from those I knew it was the fuel injector. When I came to a stop the engine would start misfiring at cyl 1, but would start firing normally once I put the gas on. It also started surging when under any type of acceleration. I replaced the coil packs and spark plugs (NGK .28 gap platinum) about 2 weeks ago because on of my coil packs died. kept troubleshooting and was able to replicate the misfiring while under the hood with the engine running from fiddling with the plugs that go to the injectors. I've been driving a lot in the city recently and I think all the bumpy roads were slowly dislodging the plugs since they dont lock down.

After pressing all the injector plugs down, I know longer have any surging or cylinder misfires. So now im just wondering where I can get some new plugs to splice in as these will just surely get dislodged again when I'm driving in the city again. Also, oddly enough, I think u was getting more boost when the plugs were loose. Maybe the ECU was compensating somehow, but very randomly the computer would comply with my foot all the way down on the pedal and give me 18psi boost. Now, with the plugs snuggled in tight, it feels more like 12psi, haven't looked yet. I'm hearing that flutter though when you quickly release the gas. Bad diverter valve? Where can I buy an aftermarket diverter? Also where can I get electrical parts? Specifically, for wiring, where you push the connector on and the plastic housing locks on. Most of my plastic housing for the connectors are broken and don't lock on: diverter valve, knock sensor, all 4 coil packs, probably more.

You can buy just the plug itself. https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/2-pin-connector-priced-each/443906232/ It takes as special tool, or paperclip, or small screwdriver to remove the terminals. It really depends on what exactly the problem is with the wiring.

Also, how do you know when you need a new battery? It charges up to 14v and goes down to 12v pretty fast if I'm just sitting in there with the stereo on. Also I can make my engine skip a beat when I roll the window up on an already rolled up window. And the headlights visibly dim at the same time too. What's up with that?

Also, the back seat floor is wet. I thought I fixed that a long time ago because I did clear the holes of debris that's under the battery, but when it started raining again I noticed the problem wasn't fixed. Now I'm fairly certain all the foam underneath will be moldy and I dont know what electricals may be interfered with down there.

Also, when my car is jacked up on the driver side front wheel, I can jiggle the wheel back and forth. It's the upper left joint I think, so I bought two new ones and the tool to pry it off. I just dont know the procedure, I'll try to look it up. But it's pretty bad. I have to hold my steering wheel at 11 o clock to go straight.

When you jiggle it, can you see play where the arms come together? If there is no movement where the arms come together, it could be a wheel bearing.

Also, hard shifting. Most frequently when coming to a stop and it shifts from 2nd to 1st. Don't say tranny don't say tranny. It used to fairly rarely shake the whole car when shifting from 4th to 5th, but hasn't happened for a while, which makes me think its vacuum related. I really need to replace all those check valves.

Also, I've checked on my pancake valve, or pressure regulating valve, and its been drippy with light brown liquid. It's not thick, it's not watery though either. But is it normal for the PCV system to be more that moist?? Its literally dripping fluid into the larger tube from the pancake valve.

Yes, that is normal for these engines. I just clean mine out once in a while. It doesn't really get stopped up like the PCV bleeder valve, or suction jet pump

Sigh... not even the half of it. Runs pretty great though. Anyone in Washington that can help me?
Some answers in red for you.
 
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