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6

The Purge is controlled by the PCM with a pulse width modulated switch signal. It is normal for it to cycle rapidly. This allows small amounts of the fuel vapor to be metered into the cylinders. This method allows the system maintain fuel control. One of the main jobs of the evaporative control system purge valve is to maintain a slight negative pressure ...


3

Yup, you can replace it with generic hose.


3

The test connectors are common on Subaru vehicles. They put the car is diagnostic mode and allow for things like the ECU to be reprogrammed. I actually have a Saabaru and had to connect these to use a Cobb Accessport. While it was connected I also had fans and other items turning on and off randomly. Would need some context for the instructions in ...


2

In an answer to your linked question, Larry suggests that the indicator light could be coming on due to a loose gas cap, a torn hose or a leaking seal. Remember how the system works: When the right conditions are met IE fuel level between 1/3 and 1/2 tank, outside temp 50 - 90 etc. the ECM pulls a vacuum on the evap system and makes sure it holds a ...


2

There are a lot of things that can set this code, so it can be time consuming to figure out, and there are some special tools that make the job a lot easier. You can do it without the special tools, it's just going to take longer. The list below is what it takes to set the code. When VSV for pressure switching valve is ON, ECM judges that there is no ...


2

I doubt anything is wrong with your powertrain controller. It sounds like it's doing what it's supposed to, monitoring the EVAP system and throwing codes when it sees a problem. The problem went away or the check engine light would not have gone off. Some trouble codes can be self resolved like that (so many drive cycles without a problem, the light goes ...


2

The cars' computer runs tests on the emission systems on the car. When the car fails the test it turns on the light, if it passes the test after that it turns off the light. You may have something that is close to failing the parameters set by the OEM. A small leak that's just on the edge of passing. Something like temperature changes, or vibration could ...


2

It is most likely a leaking EVAP hose or a leak in the fuel line. Make sure it's nothing obvious like a hose hanging off or a gas cap missing. Also check for a check engine light and have the OBD code read if there is one. There is also a small chance that your fuel pump relay or fuel pump is the cause.


2

This situation could be Transmission Flare. The engine control briefly ups the RPM to match the transmission downshifting, to prevent an abrupt downshift feel. If the control or sensing systems are out of whack, it can overdo the RPM adjustment. Some of the items you replaced require adjustment or calibration. For example, the Idle Air Controller (a prime ...


2

Slow or no flow for fuel in means no or low vapor flow out the vent system. Steps to test for testing for a blocked vent: Remove the CAN VENT fuse, #64 in the Underhood Bussed Electrical Center (UBEC). Recheck fuel fill. If now OK, check the White evaporative vent solenoid wire for a short to ground, between the evaporative vent solenoid on top of the ...


2

Check for an exhaust leak before or right after the o2 sensor, have someone use a rag and plug the exhaust while you listen. Or smoke test the exhaust system. Also check for vacuum leaks or any other lean/rich condition that would drive the o2 sensor in one direction or another. If you don't find an exhaust/vacuum leak you'll want to back probe the sensor ...


2

The difference is regulatory not technical. P0133 is the SAE generic version. It satisfies the USEPA and CARB that this failure is covered under a code and conforms to regulated descriptive language. P1133 is the GM version that is used in the their diagnostic system. Both have the same failure criteria.


2

From http://o2sensors.com.au/static/o2-sensor-identification-and-locations : So what is Sensor 1? Sensor 1 is the O2 sensor that is located before or upstream of the catalytic converter. (Pre-cat) So then if your diagnostic code is B1 S2 that means Bank 1 Sensor 2 down stream (post-cat). If its B2 S2 that means Bank 2 (opposite Bank to Bank 1) ...


2

The most typical system used by GM is a vacuum decay type system. The system has 3 major components (for leak detection that is); purge solenoid, vent solenoid and a pressure sensor. Under normal operation, the vent solenoid is open and allows air both in and out depending on the situation. The vent solenoid is connected to the outlet of a charcoal ...


2

The code P0456 indicate a leak that is not so severe, compared to a P0455. Since you already replaced the fuel cap, so the problem can be in many other parts of the fuel system that can be very painful to diagnose. It should be ok to drive like that, but keep an eye to see if the code is not "promoted" to P0455 or if the leak is noticeable (visually or by ...


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Don't know if this helps; best I could find...


2

The tank should be vented, and done properly it should vent into a canister. The purge line to the carb is less important, but a hole in the carb under the butterflys is likely creating a vacuum leak. I can't speculate why people remove things like that. Probably an imagined performance gain unlocking hidden horsepower by removing all those evil "...


2

I found this PDF with Drive Cycles for Hyundai's, which should include your Veracruz. Here are the relevant parts of the Drive Cycle to include the graphic from the PDF: General Instructions: Drive Schedule Notes: Coolant needs to be within 0 to 40C (0 to 104F) at start Fuel level must be above 15% (Pᴀᴜʟsᴛᴇʀ2 Note: I've seen a lot of ...


2

I wanted to followup on this one, in case anybody else gets here. Brief review: In many (all?) states within the USA, an annual emission / SMOG test is required at the time of registration renewal. In my state, they follow the guidance from the federal Environmental Protection Agency (EPA) concerning readiness during OBD II inspections. In simple words, ...


1

If you apply the smoke to the pipes and sensors for extended periods of time (weeks or months) then most likely yes. However, for a 1 off short period to find a fault probably not - this does assume that the oil used to make the smoke is compatible with all sensors & seals...


1

Normally, pressure that develops during filling the gas tank is relieved by venting to the atmosphere via the filler tube (some locales require filler nozzles to be equipped with vapor recovery, in that case the fill nozzle seals to the filler neck and vapors are sucked/pumped back into the filling station tank). The evap system is designed to scavenge ...


1

TL DR: Most likely this is not an issue, but rather the EVAP system at work. Every emissions controlled vehicle has an EVAP system which controls the amount of fuel which is exhausted to the atmosphere from the fuel system/tank. The EVAP system can test itself one of two ways, either through pressure in the tank or vacuum. Either pressure or vacuum will ...


1

The canister is filled with activated charcoal, which is very effective at storing fuel vapors. Effective enough, in fact, that no fuel smell is detectable before the canister is purged by fresh air into the engine. Well, that's the standard reason why. There are some that may argue that no fuel vapors escape because EVAP systems are totally useless... But, ...


1

First of all, it looks like my fuel tank has a separate "breather" hose separate from any kind of "EVAP" system. I can see it coming out from the bottom of the vehicle, and I'm guessing it probably connects to some compartment somewhere inside the top of the fuel tank (i.e., somewhere at least above the fuel level). I'm thinking this is probably an overflow ...


1

You can check the vacuum line for the purge valve and the related connector. If you follow the under hood vacuum diagram, it'll lead you to where the valve is. More than likely it's just a coincidence. If you've gotten gas lately, it could be a loose gas cap. If they provided you with the DTC than it may help point to what went wrong. An unplugged purge ...


1

Any competent refrigeration engineer / shop can sort a suitable replacement and they will be able to match fittings etc.


1

Well there was a vacuum leak. Plain and simple logic dictates a drop in fuel efficient performance as the gases are not being recycled as the Evap system would when it's running without leaks at optimal efficiency. The moment you ran the test and fixed it, your problem vanished. Now the theory with the check engine light is accurate in your case as it ...


1

Leaks in the evaporative system can be challenging to find. A "large leak" can be a hole as small as .040" in diameter. Common leaks on this model are: Fuel Filler Cap Canister Drain Cut Valve (CDCV) also called the Canister Vent Valve Purge Solenoid/Valve Pressure sensor Testing is most commonly done by filling the system with smoke from a smoke ...


1

I removed the top hose (engine to canister) and drove. I still experienced the run-on, so I believe this conclusively rules out the canister as the cause of the dieseling. I also found that the connection of this top hose to the metal tubing was very loose and possibly the cause of the gasoline smell. I put a hose clamp here to eliminate this. As far as ...


1

Yes it can. You can find it as either DORMAN Part # 911603 or as AIRTEX / WELLS Part # 2M1257.


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