Great
Are the Bosch part number on the side the same on both map sensors
Forget about the serial numbers
The
0261230030
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Technical Slow picking up
- Thread starter l33rsk
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Technical Slow picking up
Are the Bosch part number on the side the same on both map sensors
Forget about the serial numbers
The
So original map
Ignition on reads KPA
New map
Ignition on does not read KPA
Make sure the electrical connector pushed on the same amount they can be quite firm
But without at least a KPA reading at ignition on with the replacement MAP we cannot move forwards
Ignition on reads KPA
New map
Ignition on does not read KPA
Make sure the electrical connector pushed on the same amount they can be quite firm
But without at least a KPA reading at ignition on with the replacement MAP we cannot move forwards
I’ve just purchased another map sensor from somewhere else this one was obviously faulty with it throwing a fault code connector on firm and yellow tab locked down I did try it a few times still same result.
Sorry to hear that. Very disappointing.
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Is this "another map sensor" the third, so the two new ones give a fault codes, or is it just two sensors and the second one throws a code?
It's a shame you haven't access to another, similar Panda. Then you could have tested them all in the other car.
Yes purchased a second but not arrived yet should be here the weekend. Thanks
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I was rereading some of this thread yesterday and one of our contract engineers was in the office.
He builds and tunes stock cars and track cars for himself and others.
He pointed out if everything is even, the MAP reading will be even.
If all cylinders are all equally good (or bad if the timing was out), the MAP will read steady.
(We obvious need to trust the MAP is good though)
As you can see in first image below, the "good" graph Koalar posted, the reading is steady.
If one cylinder is off, say a broken valve spring, bad valve seat etc, the MAP will drift. It will try to push up.
How much depends on how bad the issue is, but as each cylinder drops, the iffy one won't pull the same and cause it the MAP to drift.
You can see in the second image, it's drifting up.
(This one was because of a broken valve spring)
The inlet pressure will pulse, but the pulse average should be steady and not drift.
We discussed testing this out and he reckons a drift will be easier to spot with a crank test as the crank speed will be lower and the pulses slower.
Though going direct to a compression or leak down test if you had the kit would tell you the same thing.
To do a crank test.
Make sure the battery has good charge, pull the fuel pump fuse and run the engine until it stalls.
Log and record the MAP while you crank the engine over for 8 seconds or so.
It would be better to try and log it as a graph, as it will be easier to spot any meaningful drift.
Also without the engine firing, you aren't producing a load of hot, expanding exhaust gas and sending all that down the exhaust through the Cat..
It's just pumping the air it's sucked in, which is a lot less that that expanding hot gas.
So if the Cat or exhaust was partially blocked and your high MAP reading was because all the exhaust is backing up, taking all that expanding gas away should show if the MAP reading drops towards expected value.
He builds and tunes stock cars and track cars for himself and others.
He pointed out if everything is even, the MAP reading will be even.
If all cylinders are all equally good (or bad if the timing was out), the MAP will read steady.
(We obvious need to trust the MAP is good though)
As you can see in first image below, the "good" graph Koalar posted, the reading is steady.
If one cylinder is off, say a broken valve spring, bad valve seat etc, the MAP will drift. It will try to push up.
How much depends on how bad the issue is, but as each cylinder drops, the iffy one won't pull the same and cause it the MAP to drift.
You can see in the second image, it's drifting up.
(This one was because of a broken valve spring)
The inlet pressure will pulse, but the pulse average should be steady and not drift.
We discussed testing this out and he reckons a drift will be easier to spot with a crank test as the crank speed will be lower and the pulses slower.
Though going direct to a compression or leak down test if you had the kit would tell you the same thing.
To do a crank test.
Make sure the battery has good charge, pull the fuel pump fuse and run the engine until it stalls.
Log and record the MAP while you crank the engine over for 8 seconds or so.
It would be better to try and log it as a graph, as it will be easier to spot any meaningful drift.
Also without the engine firing, you aren't producing a load of hot, expanding exhaust gas and sending all that down the exhaust through the Cat..
It's just pumping the air it's sucked in, which is a lot less that that expanding hot gas.
So if the Cat or exhaust was partially blocked and your high MAP reading was because all the exhaust is backing up, taking all that expanding gas away should show if the MAP reading drops towards expected value.
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2nd New map sensor arrived today and fitted no eml light. Kpa reading with just ignition on is 104 compared to original which was 100. When car warmed up to temperature with new map still fitted at idle is 45kpa short term fuel trim now maxed out at -100% and not moving which is worse than original sensor which was oscillating but never got up to -100%.
O2s1 is now stuck around the 0.84v and not dropping below 0.8v.
O2s2 is now stuck at 0.90v. So this to me is worse than before with the new sensor which is obviously reading more accurately as it’s new. Thanks
Thanks for the update. It another ticked off the list.
The fact it reads right at ignition on probably points to the grounds power and ECU are okay
It’s was always going to a long shot
Did the new MAP come with the green o ring pre fitted
It could just be me but I think valve timing really needs looking at again .....yes again.
Including removing valve cover to see if number4 cylinder valves are both equally partially open when engine cylinder 1 at tdc .
I have come across engines where the cam pulley marks are miles off due to the key being crushed/ torn off.
Plus maybe run engine without aux belt on and check readings - excessive load from alternator for instance will affect expected map reading- though shouldn't cause o2 sensor problems
Including removing valve cover to see if number4 cylinder valves are both equally partially open when engine cylinder 1 at tdc .
I have come across engines where the cam pulley marks are miles off due to the key being crushed/ torn off.
Plus maybe run engine without aux belt on and check readings - excessive load from alternator for instance will affect expected map reading- though shouldn't cause o2 sensor problems
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Yes it did have the green o ring already fitted. Thanks
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The 104 atmospheric is about right today.
My local airport is reporting 103 and that's at sea level.
The new MAP is seeing 45 instead of 40ish, which looks like it's now trying to fuel for, more of one equals more of the other, due to this the O2 has gone even richer.
You have to start thinking is the 40 to 45 right.
It looks like it is far too high from what we know of other Pandas.
So now you have to find out why.
Why isn't it pulling down low enough at idle
My local airport is reporting 103 and that's at sea level.
The new MAP is seeing 45 instead of 40ish, which looks like it's now trying to fuel for, more of one equals more of the other, due to this the O2 has gone even richer.
You have to start thinking is the 40 to 45 right.
It looks like it is far too high from what we know of other Pandas.
So now you have to find out why.
Why isn't it pulling down low enough at idle
I also did a test at 2000rpm and it only went down to a steady 33kpa also did the same test but watching short term trim and it stayed at a steady -100% I’m not sure at all what’s going on. Thanks.
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Ok, your engine is a big pump but the air it can suck in is variable. The throttle body controls that.
The throttle body controls the air it can suck in but in between the pump and the throttle body is a container, the inlet manifold with the MAP sensor in it.
At idle the big pump should create a big negative pressure inside the container as the hole in the container is limited (by the ICV and closed throttle plate).
There appears to be a problem with it doing this, but why?
Is there a problem with the container, say a hole in it that shouldn't be there or a problem with the throttle plate or ICV?
Is there a problem with the big pump so it pumps less than it should do, like a piston or chamber seal problem or it can't expel the pumped air?
We don't think it's the first hole problem as the revs would increase, just as they would opening the throttle plate.
So is there a problem with the big pump. Is something effecting it's ability to suck in the air or expel it out?
This could be a cylinder seal problem, like the valves being open at the wrong time (timing out) or an issue with. cylinder sealing, like a broken valve spring or worn valve seat.
The throttle body controls the air it can suck in but in between the pump and the throttle body is a container, the inlet manifold with the MAP sensor in it.
At idle the big pump should create a big negative pressure inside the container as the hole in the container is limited (by the ICV and closed throttle plate).
There appears to be a problem with it doing this, but why?
Is there a problem with the container, say a hole in it that shouldn't be there or a problem with the throttle plate or ICV?
Is there a problem with the big pump so it pumps less than it should do, like a piston or chamber seal problem or it can't expel the pumped air?
We don't think it's the first hole problem as the revs would increase, just as they would opening the throttle plate.
So is there a problem with the big pump. Is something effecting it's ability to suck in the air or expel it out?
This could be a cylinder seal problem, like the valves being open at the wrong time (timing out) or an issue with. cylinder sealing, like a broken valve spring or worn valve seat.
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The O2 is detecting rich as the MAP is reading less intake pressure than it should and it adds fuel to match that air.
That then burns rich which the O2 sensor sees and tries to trim out
If you are worried about the O2, if you did the crank test and disabled the fuel pump, it should just detect air and shift from rich to lean.
That then burns rich which the O2 sensor sees and tries to trim out
If you are worried about the O2, if you did the crank test and disabled the fuel pump, it should just detect air and shift from rich to lean.
I am still surprised it not timing ?
Sounds like timing
Behaving like timing
Sensor read like timing
The car stood for long periods which is known to cause the timing to jump
How much do we trust the garage actually checked it ?
Sounds like timing
Behaving like timing
Sensor read like timing
The car stood for long periods which is known to cause the timing to jump
How much do we trust the garage actually checked it ?
