2.5 dse auto Power loss..?

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wammers said:
Sorry Keith don't want to fall out with you but what you claim is not possible. With the Map sensor pressure pipe disconnected there will be a significant power loss and throttle response lag above 2000 RPM.
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You can argue all day, two cars are unlikely to have the exact same fault and they both run as near as makes no difference normally with the pipe off. I can't argue with results, you may be able to.
Why don't you try it on your car assuming it's the same vintage?
 
Datatek said:
You can argue all day, two cars are unlikely to have the exact same fault and they both run as near as makes no difference normally with the pipe off. I can't argue with results, you may be able to.
Why don't you try it on your car assuming it's the same vintage?
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Keith i am not arguing i am stating a fact. Vintage is of no consequence. You carry on you obviously know best.
 
wammers said:
Keith i am not arguing i am stating a fact. Vintage is of no consequence. You carry on you obviously know best.
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I do not have your 50 years of experience and consequently fixed ideas of what should happen, I come to things with an open mind and report what actually happens, I do not profess to know exactly why it happens although I have a shrewd idea. You can deny as much as you like but what happens happens.
 
Datatek said:
I do not have your 50 years of experience and consequently fixed ideas of what should happen, I come to things with an open mind and report what actually happens, I do not profess to know exactly why it happens although I have a shrewd idea. You can deny as much as you like but what happens happens.
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You have had it explained believe it or not as you wish. You CANNOT have turbo boost if the MAP sensor is disconnected. So what is your shrewd idea enlighten me?
 
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wammers said:
You have had it explained believe it or not as you wish. You CANNOT have turbo boost if the MAP sensor is disconnected. So what is your shrewd idea enlighten me?
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You and I approach these things from totally different directions Tony. If I see something happening that does not fit my expectations, I go looking for why that should be. You prefer just to deny based on your knowledge without questioning why something should happen.
It's too bludy cold to work on the car at the moment, so I'll come back to this if and when I find out what is behind what is happening.
 
Datatek said:
You and I approach these things from totally different directions Tony. If I see something happening that does not fit my expectations, I go looking for why that should be. You prefer just to deny based on your knowledge without questioning why something should happen.
It's too bludy cold to work on the car at the moment, so I'll come back to this if and when I find out what is behind what is happening.
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It's a miracle mate it has to be unless the manifold is using telepathy to tell the MAP sensor what it's internal pressure is.
 
Datatek said:
I'm not going to argue, but the fact is I have 2 P38's that run with the pressure pipe disconnected, no noticeable difference when the pipe was replaced.
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Sorry bud, mine will run without the map plugged in also. I had that funny rattling noise from fip, when i ran it unplugged from the map sensor the rattle stopped. But and i say but! Op, listen up. I have since replaced my in tank and pump head o'ring and the engine runs much better and the rattle has gone!! Mine will run with both the map and maf unplugged.. but not tried since the last repairs were carried out.;)
 
Mark Piercy said:
Sorry bud, mine will run without the map plugged in also. I had that funny rattling noise from fip, when i ran it unplugged from the map sensor the rattle stopped. But and i say but! Op, listen up. I have since replaced my in tank and pump head o'ring and the engine runs much better and the rattle has gone!! Mine will run with both the map and maf unplugged.. but not tried since the last repairs were carried out.;)
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The MAP was not unplugged, just the pipe was off. In tank pump is new on one car and working on the other and no FIP leaks on either.
 
Mark Piercy said:
Sorry bud, mine will run without the map plugged in also. I had that funny rattling noise from fip, when i ran it unplugged from the map sensor the rattle stopped. But and i say but! Op, listen up. I have since replaced my in tank and pump head o'ring and the engine runs much better and the rattle has gone!! Mine will run with both the map and maf unplugged.. but not tried since the last repairs were carried out.;)
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Of course it will run, with the pipe off but you will not get any turbo boost fuel.
 
Well, opened the tank and removed the gubbins, more muck than a school kitchen U bend in the white plastic housing... removed the filter bag and soaked everything thoroughly with petrol, drying overnight in the shed now and will test drive it in the morning, but I'm pretty sure that must have been it, the inside of the housing was 5mm thick with black sludge and the filter bag on the bottom of the pump looked like it just crawled out of a swamp!
 
Wazzajnr said:
If the map is unpiped, will the ecu not use a default engine mapping and run more or less normally?
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Mine ran and drove ok with plug removed from the map as it stopped the fip from rattling?? . It did boost but with a little less errr boost!
Weeeeelllll......
Hopefully our man has hit the nail! Regardless of our experiences ..o_O;)
 
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Have very low power on my 98. It has a cone air filter, tbh not delved into it too much, as didnt really realise how bad it was till other day. Have no egr valve, no maf sensor. Has a silly cone air filter on. The intercooler to inlet manifold hose is very soft. There is also an oily residue on the turbo to intercooler metal pipe. There is a non return fitted in the fuel line just before the FIP, It does need a bit of oil adding as just on the minimum. There is also an oily deposit around number 1 injector. I think i will be changing the leak off pipes, as all seem towards the end of their life, but not appear to be leaking diesel. Ecomomy is also only around 17mpg, but I do mainly a 4 mile eack way commute to work.
Only had the car a little over 6 weeks. My 200 and 300 tdi discos go a lot better, and the 300 has not been fiddled with and running big lift and tyres. Pulling out of junctions has definatly got more "challenging".
I have read various threads on here and BMW forums about various power issues, and tuning procedures. But info on amything relating to the m51 lump is a blit like rocking horse ****.
 
egor8384 said:
Have very low power on my 98. It has a cone air filter, tbh not delved into it too much, as didnt really realise how bad it was till other day. Have no egr valve, no maf sensor. Has a silly cone air filter on. The intercooler to inlet manifold hose is very soft. There is also an oily residue on the turbo to intercooler metal pipe. There is a non return fitted in the fuel line just before the FIP, It does need a bit of oil adding as just on the minimum. There is also an oily deposit around number 1 injector. I think i will be changing the leak off pipes, as all seem towards the end of their life, but not appear to be leaking diesel. Ecomomy is also only around 17mpg, but I do mainly a 4 mile eack way commute to work.
Only had the car a little over 6 weeks. My 200 and 300 tdi discos go a lot better, and the 300 has not been fiddled with and running big lift and tyres. Pulling out of junctions has definatly got more "challenging".
I have read various threads on here and BMW forums about various power issues, and tuning procedures. But info on amything relating to the m51 lump is a blit like rocking horse ****.
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From your information your car sounds like a bit of an abortion. Is it manual or auto?
 
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