[VictorRee]

Long-time reader, first time poster, and not mechanically minded.

I have a 2011 auto Jimny that at last service was diagnosed with exhaust manifold cracks. Had been running with reduced power & increased fuel consumption so thought the cracked manifold/cat may be the cause, in part at least. Was decided to source non-genuine manifold & cat.

New non-genuine manifold & cat installed, & collected from mechanic for 20 klm run home at 100 klm per hr in parts. Following day 20 klm run to work at 100/110 klm per hr, engine management light on during deceleration off highway. Returned to mechanic for review.
New non-genuine manifold & cat installed, same run home & same following day run to work with engine management light on during deceleration off highway. Returned to mechanic for review.
Old genuine manifold & cat welded & re-installed, same run home & same following day run to work with engine management light on during deceleration off highway, at virtually the same spot +/- 10 metres.

Was hoping someone out there may have had similar issues &/or can put me in the right direction as to possible causes, things that we should be checking etc.

Have missed a 2 week trip to Fraser because of this, as well as being without the vehicle for an extended period of time while attempting to sort issue.

Have used mechanic for a number of years (not a Suzuki specialist) with excellent/good value results prior to current issue.

Any guidance would be greatly appreciated.

[fordem]

Have you considered checking the codes to see why the engine management light comes on?

[VictorRee]

fordem wrote:

Have you considered checking the codes to see why the engine management light comes on?

I would assume the mechanic is doing that each time but will discuss with him & post up codes.

[Gwagensteve]

You mechanic is letting you down. The car is trying to tell you what is wrong with it- pull the trouble codes and fix that.

[VictorRee]

Gwagensteve wrote:

You mechanic is letting you down. The car is trying to tell you what is wrong with it- pull the trouble codes and fix that.

Is there a recommended diagnostic reader?

[Beery]

There's lots of cheap/generic scan tools around, however they're a bit limited in what they can do, but can be somewhat useful for some situations. If you're mechanic doesn't have a proper scan tool, ( A proper scan tool with a wide variety of capabilities is thousands of dollars) then that's the first issue. The second issue, is that a lot of mechanics put too much trust in their scan tools - scan tools aren't a magic box that tells you exactly what's wrong with the car. they point you in a direction and diagnoses continues from there.

If you're not mechanically minded, buying a cheap scanner, reading the code(s) and replacing something that's somewhat related to what pops up on the screen will typically just end up in throwing parts and money at the car with no real outcome. It might be a simple problem, it might not be, but your best shot is to find a mechanic who has a scan tool and can diagnose - I know that sounds simple, but diagnosing problems can be difficult. In my area, 90% of mechanics spend their days doing services, wheel bearings and throwing spark plugs and leads at every car that comes in with a misfire - very few can diagnose even mild problems.

[VictorRee]

Code is the same each time & EGR related. Getting scanned again tomorrow so will have the exact code. Likely a faulty EGR valve?

[Gwagensteve]

Time to consult the factory service manual and follow the troubleshooting guide for that code.

[fordem]

Were you getting the check engine light before the work was done on the exhaust manifold? If the answer is yes, were the codes EGR related.

The exhaust manifold is a part of the EGR system - it routes exhaust gasses from the #4 cylinder to a port in the head that feeds over to the intake side and then through the EGR valve to the intake manifold.

[VictorRee]

No engine light on before work done on exhaust manifold - cracks (many) to exhaust manifold noted during rego. check & reduced performance & increased fuel consumption noted over time - it may be that the EGR valve was on the way out & work performed is coincidental to valve failure or pushed valve to failure (assuming this is the problem).

[royce]

A lot of OBD11 codes often don't relate to what it sounds like just reading the short description, you really need to check the manual for the longer meaning and troubleshooting process to work it out.
As I was reading this thread I thought to myself I bet its an EGR code before I even got to your post about the code, M series are a bit finicky with EGR flow and how it calculates it.

Based on the (very little) info you have passed on, I am going to throw a hunch at the aftermarket manifold either not have the EGR supply tube that runs from the cylinder 4 exhaust branch to the EGR port in the head or it being very small or badly sealed and leaking.

Can you find out the exact code (will start with a P then 4 digits) to look up in the manual, along with post some good clear pics of the new manifold and the area between runnr 4 and the back of the engine and EGR valve?

Also, Code P0401, P0402, P0403 will not effect driving performance or economy at all, if you need to take the car somewhere, do it!