Genuine vs Not Genuine parts

[sharklaar]

I'm looking at replacing my MAF and MAP sensors, but I'm on a super-tight budget. The price difference is fairly massive - I can get both parts, brand new on the cheap for a total of about £65..

Obviously you get what you pay for though, what are the downsides of doing this? I'd expect perhaps shorter longevity perhaps, but is a copy part likely to perform poorly? Cheers

[ajm]

I wouldn't even consider using a cheap MAF sensor. I did - and regretted it immediately as it was useless. Ended up buying a genuine Bosch from a company selling through EBay (from Germany if I recall correctly.) It still wasn't cheap but it was considerably less expensive than UK based sellers were retailing them for...

(Edit to clarify; it was useless in that the fuelling was actually worse than when the MAF sensor was unplugged!)

[sharklaar]

Originally Posted by ajm

I wouldn't even consider using a cheap MAF sensor. I did - and regretted it immediately as it was useless. Ended up buying a genuine Bosch from a company selling through EBay (from Germany if I recall correctly.) It still wasn't cheap but it was considerably less expensive than UK based sellers were retailing them for...

(Edit to clarify; it was useless in that the fuelling was actually worse than when the MAF sensor was unplugged!)

So basically a cheap one was worse than a knackered one then... Righto, I'll get saving. Likely to be the same for a MAP sensor too I guess...?

[cheshired5]

Before buying a MAF, watch this https://m.youtube.com/watch?v=QtQnE1QW-jU

Also, test your sensors with cheap diagnostics.
On what basis are you changing them?
MAF and MAP pretty much never fail together.

[sharklaar]

Originally Posted by cheshired5

Before buying a MAF, watch this https://m.youtube.com/watch?v=QtQnE1QW-jU

Also, test your sensors with cheap diagnostics.
On what basis are you changing them?
MAF and MAP pretty much never fail together.

Interesting video, cheers! I'll check mine out.

Did you see the diagnostics I posted in my other thread recently from the OBD reader? What I took from the air flow figures is that there is an air leak between the MAF and the turbo, although because the problem is intermittent, I'm guessing the sensor is knackered. I'm not a mechanic or an engineer, but this seems reasonably logical - intake PSI is constant at 1 bar through the rev range, but air flow increases (although is very low compared to your readings). Can't see an issue with any of the hoses, and the intake hose is solid ( I gather this can go soft and cause intake problems).

MAP sensor, I'm considering replacing on the basis of other posts... when I'm not experiencing the intermittent air flow problem, the performace isn't great - up to 2.5krpm i get no boost, and it kicks in very suddenly, above 2.5k it really pulls, but nothing below that. A couple of other posts suggested that replace/clean of MAP fixed it.

There's my unqualified reasoning behind it. Also they look easy for a muppet like me to change, and not too expensive. Especially considering what your video says

[cheshired5]

Originally Posted by sharklaar

Interesting video, cheers! I'll check mine out.

Did you see the diagnostics I posted in my other thread recently from the OBD reader? What I took from the air flow figures is that there is an air leak between the MAF and the turbo, although because the problem is intermittent, I'm guessing the sensor is knackered. I'm not a mechanic or an engineer, but this seems reasonably logical - intake PSI is constant at 1 bar through the rev range, but air flow increases (although is very low compared to your readings). Can't see an issue with any of the hoses, and the intake hose is solid ( I gather this can go soft and cause intake problems).

MAP sensor, I'm considering replacing on the basis of other posts... when I'm not experiencing the intermittent air flow problem, the performace isn't great - up to 2.5krpm i get no boost, and it kicks in very suddenly, above 2.5k it really pulls, but nothing below that. A couple of other posts suggested that replace/clean of MAP fixed it.

There's my unqualified reasoning behind it. Also they look easy for a muppet like me to change, and not too expensive. Especially considering what your video says

Have you blown onto your MAF to see if it can register higher airflow figures?
You can use a hairdryer too from varying distances.
Same with the MAP. Take it out, clean it up, blow into it and suck on it to see if it registers pressure and vacuum on your diagnostics.
Regardless of whether money is tight or plentiful, free, quick and easy troubleshooting first I say.

[sharklaar]

Originally Posted by cheshired5

Have you blown onto your MAF to see if it can register higher airflow figures?
You can use a hairdryer too from varying distances.
Same with the MAP. Take it out, clean it up, blow into it and suck on it to see if it registers pressure and vacuum on your diagnostics.
Regardless of whether money is tight or plentiful, free, quick and easy troubleshooting first I say.

Sweet, I'll give this a go before splashing out any dollars. Ta!