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Discussion Starter #1
Hi All,

I have been suffering from power loss for a while - i put my foot down and its like driving a slug and expecting acceleration... I have been reading a lot on this problem as many 3.18i owners seem to have it. One of my major suspects is the MAF after trying/replacing some other things.. so within the last hour i have just done the following:

1. Tried disconnecting the MAF while the engine is running expecting it to stay running (according to what i have read) but it cut out - this isn't right for starters is it?

2. restarted the car without the MAF connected and is started fine so i went for a drive. IMMEDIATELY, i noticed the power difference it was all a little jerky at first but i put my foot down and the car flew through the first couple of gears... to the point where your stomach turns not expecting to go that fast (if you know what i mean).

3. Drove for about half a mile like that then i noticed that the auto changing was getting rather heavy and it would THUMP going down into first gear. I didn't like that, it was actually a bit worrying so i stopped the car and plugged the MAF back in. (Why would the gear shifting change like that without the MAF? ) - With the MAF back in the car went straight back to normal, sluggish but absolutely no thump in the gear change... phew!!

4. Got back home and cleaned the MAF with contact cleaner put it back on but it made NO noticeable difference.

5. While the engine was running i unplugged the MAF again but this time NO cutting out, the engine just seemed to adjust a little.

6. I left it unplugged and drove it like this one last time and sure enough the power was back again!... not smooth but definitely back. The clunky gear changing wasn't there but i only went around the block a couple of times.

One las thing;

7. just remembered is it normal to unplug the MAF and have the dash light turn on next to the 'P' (park) that looks like an orange cog with an exclamation mark in it? according to the manual its an Automatic Transmission fault light causing the transmission to switch to the emergency-run program??


After all my research on the net and this result makes me confident that part of my problem is definitely a faulty MAF. Some of what happened i didn't expect but you guys have much more experience I'm sure, so please give me your thoughts?

much appreciated

Jason
 

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I'd say a faulty MAF too , disconnecting the maf while the engine is running will cause it to stall in most cases, starting without the maf will force the engine to run off the Lambda and the throttle position , this will make the car jerky but it gets the right airflow (faulty maf causes the engine to think that it recieves less air than it actually does)
 

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Discussion Starter #3
Thanks for the post mate! your info helps a lot... does the jerkiness suggest a faulty lambda/throttle position sensor or would the car jerk regardless of the condition of the sensors ?
 

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Discussion Starter #4
Update!! Problem Solved :)... well at least one! Woohoo!

I ended up buying a new MAF from:

http://www.emissioncontrols.co.uk/

The website doesn't look like much but the price was £159.00 inc next day delivery for an original Bosch MAF (dealer £280.00) - replaced it straight away and i couldn't believe the difference, my little 1.9 engine did me proud and put a big smile on my face! The power was there like never before... Fantastic!

However, my EML light is still on, i'll plug in the pc tomorrow and see what's happening... Then it'll be on to the next problems... getting rid of the EML light once and for all and the Airbag Light! Last but not least, find out why I'm losing coolant.

For now I'm happy!
 

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Good for you! Keep us posted on everything ok.

Here is a post where the solution of the problem was later told by e46fanatic, I hate those posts where there is a lot of opinions and get to no where because the person who started the post never took the time to get back on to tell what was the solution, fix, etc. You are the man Jayp07
 

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Discussion Starter #6
Cheers mate! That's exactly why i did the update... hopefully this may help someone else! I'll post up what happens next when i get a chance to get back to the car and run a diagnostic check! Until then...
 

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Also, I'll just say that you cleaned the maf with what you call contact cleaner and I know there's a specific maf cleaner. That said, I recall reading here from someone who seemed to know, that many of these cleaners from, say CRC, are really identical, (alcohol?), but the label changes so 'we' don't worry.

But, not sure if the contact cleaner you used was right or not...not saying it wasn't, just pointing out that it wasn't a maf cleaner.

Also, there's a Hyundai MAF that's identical to ours, and obviously, much cheaper...so search for that if you're searching for a maf.

Doug
 

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Discussion Starter #9
As for the EML light it could be throttle position sensor
I'll keep that in mind, for now as the idle is spot on i'll pretend all is good until the codes tell me other wise :)

Cheers Doug - I hear what your saying mate, I don't think they differ much from what i've read. At the end of the day it just needed a good blast to shift any dirt. To be sure, I also used a paint brush. It was definitely cleaner than before but in my case nothing made a difference to the performance, that MAF was shot. I'll look into the hyundai part for the future that sounds interesting... I'm going to try and wipe the codes today and see what comes up over the weekend.
 
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