EGR visual failed smog what must i fix?

Question

1987 nissan pick-up failed smog check EGR visual inspection. i would like to no what i must do to pass the EGR visual check or what parts do i have to change.

Answer 1

that depends what part of the EGR system failed. Broken vacuum hose? If it only failed the visual inspection and not for tampering, then the EGR is there just something is either broken, not hooked up or misrouted. If it failed visual for tampering/missing or modified, then a major component is not there.Also if you live in a state like Calif. and the EGR was not hooked up and not working, You should have also failed the NOx emissions of the dyno test, unless you live in a non-enhanced county like say Santa Cruz Ca is a non-enhanced county with only a 2 speed idle test. Santa Clara County or Most of L.A or Orange county is an enhanced county.
You will know the difference by the test. Was it run on a Dynomometer? If so then you live in an Enhanced Area and you would have failed NOx Emissions also.

Answer 2

IF YOUR VEHICLE WAS ADMINISTERED THE '2-Speed, Idle" TEST READ THIS... The fact is, in this particular smog test, which is called the "Basic Smog Test" the smog machine was not actually looking at the EGR System through the engine's exhaust. Rather it had the smog technician visual and functionally inspect the EGR system through the use of a vacuum pump and/or gauge, and then had him/her enter this information into the smog machine. So actually, the smog machine had no knowledge of the EGR system failure other then the technician's input. Now, in the second type of smog test, which your vehicle was NOT administered (probably because your county does not require this test yet) the smog machine reads a third emission called the NOx (Nitrous Oxides) which eliminates the need for a smog technician to inspect the EGR system physically and instead determines whether or not the EGR system works based on the (NOx) emissions content. (NOx is almost always created when there is an EGR malfunction). In other words, had this been an "Enhanced Smog Test" your vehicle would have probably had high NOx readings and would have failed the smog test.

It appears your vehicle failed the smog inspection due to an EGR system failure. In order to better understand this failure, let's learn about the EGR system.

EGR stands for exhaust gas recirculation. The EGR system performs the function of recirculating burned up exhaust gases back into the combustion chambers via the use of an EGR valve. The fact that exhaust gases have already been in the combustion chambers once and have burned up 90% of their fuels means that, there is now much less raw fuel in the chambers to ignite. This keeps the chamber temperatures down and thus reduces NOx emissions. The EGR valve should be inspected to insure its proper operation. A working valve should be able to open its passage using manifold vacuum and/or an electronic signal. Manifold vacuum is created during the engine's intake cycle. The high demand for air during this cycle creates a vacuum within the engine's intake manifold. This vacuum is then used to control several important functions within the vehicle, including controlling the EGR valve. Some vehicles even rely on this vacuum to control their heating and air-conditioning components. In systems where the EGR valve is controlled by electronic circuits, the system needs to be inspected using a special computer scan tool.

There are a few thing which may go wrong with the EGR system. It may be possible that the EGR valve is plugged with carbon deposits and is not opening properly causing a exhaust restriction, or there may be a problem with the vacuum system which is used to open and close the valve. The method the smog tech used to determine the EGR system is defective, was by utilizing a tool called the "vacuum pump". The State requires the smog tech to attach the vacuum (hand pump) to the vehicle's EGR valve directly and attempt to open the valve manually. under normal conditions (passing conditions) this procedure should cause your engine RPM to drop at least 500 rpm's (while the valve is open). More then likely your vehicle failed the EGR visual/functional inspection because there was no significant RPM drop, for one reason or another (bad valve, clogged up passages).

My best recommendation is that you have a certified and reputable smog station diagnose the EGR system and repair the fault. Only then can the smog test be re-administered and the technician enter a "PASS" status for the EGR system.

Good Luck

Answer 3

If it is a visual then a vacuum line may be off or damage to the egr its self

Answer 4

you just need a new EGR valve on it,,it will make one fail a test,,you can get one at any parts store for around 30-50 dollars depending on what type car you have,,and for Nissan it may be a little higher than that,,but that's what they mean by what they said about it,,good luck with it,,i hope this help,s.

Answer 5

check EGR valve. Do it soon because you can damage your
cataletic converter. Also wouldn't hurt to change Oxegen sensor.

Answer 6

if it failed the visual you should be able to see what is wrong. If you paid them make them show you.

Say, if the fault is visual, show me so that I know what to fix. That is what you paid for after all.