XU7 engine pinking problem

I am still having pinking problems when cruising and only very gentle
accelerator pressure. Following advice from Mindwipe I have switched from
supermarket fuel to branded, Shell Esso Texaco etc with no noticeable
difference. I have also run a tankful of super unleaded through with only
marginal improvement.

The ECU is reporting no errors so I am beginning to think that perhaps a
sensor (MAP ??) may be sending erroneous info to the ECU but no so out of
spec to be logged as an error?

Has anyone any experience of this or any ideas?

Sadly my local Pug dealers have let me down in the past to the extent I
would not trust what they say nor their analytical skills.

TIA

Bob

 

also check the wiring to the crank position sensor as erroneous readings
from that will cause problems
last ditch is to have the ignition retarded slightlu using either diag200 or
tep 92

 

I have had two 306 with XU7 fitted. Apparrently the factory setting for the
timing requires high octane fuel (>95). With low octane fuel, it will pink.
Another problem I had was the oxygen sensor that may have a kinked wire and
partially broken away. I have had my sensor changed twice...
Your are right some Peugeot dealers are hopeless, the other day they
mistakenly thought the airbag problem was caused by connector and just cut
the connector out, replaced with soldered joint and heat shrink tube. A
second shop visit found out the problem was caused by a faulty communication
unit. Now if you want to remove the front seat, you need to cut the cable
again...
Y.W.

 

the wiring under the seats IS the weak point and they were CORRECT to solder
it
regardless of further faults this action was well worth taking

 

The wiring underneath the front seats are a bit messy, four or five
connectors under each front seat. What I am afraid of is that if you have
too many this kind of non factory mods, after a while, it will become
un-traceable even if you have some repair manuals...I did have a good look
at every connector under the seats before sending to Peugeot dealer for
repair, they all seemed to tbe OK.. Well, I probably have gone to far on
this as we are supposed to talk about pinking....

 

mindwipe wrote in message

Thanks Jeff,
I'll take a look tomorrow weather permitting. Do you know the best way to
test the MAP sensor?. Is it a resistor that varies according to vacuum?
Is the cranck sensor just a coil or is there some electronics inside to give
a digital ouput?

TIA

Bob

 

type sensor
crank sensor is 2 wire ac genertor type so look for ac output....you could
remove it clean off all the crap and refit it
if its adjustable type(you'll know if it is)then set the gap by glueing a
piece of card to it and pushing it flush (i use the box off an oil filter)
DIAG2000(TEP92) can retard ignition in .5 deg increments
just remember that if you deal with a pug dealer always ask for the master
tech and mention that your brother in leeds(thats me wink) is one
too...won't hurt

 

mindwipe wrote in message

I have located the MAP sensor and it has a good stable 5vsupply.
At tickover, the output voltage is 1.16v and gunning the throttle it peaks
at about 4 volts.
Gentle use of the throttle to soomthly raise the revs through to 4000 rpm.
and the voltage falls into the range 0.75 to 0.9 volts. At a steady 4000
(engine not loaded) it sits around 0.8v.

Would you say that this is about normal behaviour?

As for the Crank sensor, I have failed to find one. Haynes says it is on the
front face of the transmission housing but other than the reversing light
switch, I can't find anything electrical in that area at all.
Please can you give me a clue where I should be looking?
I assume it is sensing the flywheel position?

Tia

Bob

 

yes looks ok from here

it will be tucked out of site there are 2 possiblities on your engine down
the back next to the speedo sensor(rarely) and at the top right next to
where the bell housing meets the block

 

mindwipe wrote in message

Thanks Jeff,

When I was looing around the engien this morning, immediately under the
thermostat housing there were two cables with connectors held on a metal
bracket sticking out to the right (from the front of the car).. Going by
feel as I could not see anything, the rigth hand connector had nothing
connected to it (maybe the knock sensor as used by the XU10 engine?) I could
not see where the lefthand one went at all. Maybe this is the Crank sensor?
I would appear to get at it I would have to remove the air intake pipe that
comes from the grille and goes into the 'dirty' side of the air filter.
Am I getting warm?

Thanks for your help as ever Jeff, It is much appreciated.

Bob

 

bear in mind that the sensor will be fitted to meet the flywheel
if in doubt just follow it all the way round
still tink an adjustment with diag2000 will be needed though (or upgrade to
a 406 ;-)