Question about 2003 BMW Z4

Open Question

P1344 odbc misfire during start cylinder 2, after reaching normal temp, smooth as silk

Posted by on


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

What could be cause my 2001 Mitsubishi eclipse v6 3.0 liter to hesitate when first starting off and during driving after it gets warmed up? Diagnostic scan from part store reads random misfire.

Misfires are set because one of three things is wrong or missing: spark, gas, or compression. One of those is compromised to set a misfire. You just have to isolate the problem. It sounds like your engine is missing pretty consistently.
I would start with a fuel pressure test (checking the fuel pump and fuel filter). If pressure is correct, check for any air leaks around the intake manifold-the wrong fuel/air mixture in the cylinders can cause misfires.
You indicate it hesitates more after warmed up. You might try comparing the spark from each cylinder after the engine has reached normal operating temperature. It is a tedious process pulling each plug wire off the plug and then have someone crank the engine over. But you might notice a weaker spark from one or more? You would want to see a strong blue spark from each plug wire. Then you could be pretty sure the ignition system for spark is okay.
If you still haven't found it, it is time to do a compression test of the engine. You would expect all cylinders to have pretty even and balanced compression. That means full power and no hesitation, no missing. The ECU sets a misfire code because it senses the lag in crankshaft rotation-one or more cylinders is not producing the expected power output. So there's a map for you: gas, spark, or compression- which one is your engine missing.

May 27, 2015 | 2001 Mitsubishi Eclipse

1 Answer

Initial start up the engine sounds like its running on 2 cylinders under powered intil the temp gauge reads normal ???? any body got the answer please

Cold starting misfires can often be caused by either tired high tension spark plug leads or ignition coil packs. If replacing leads, then replace with a full, new set. Coils can be changed individually, but it is often the case that if one has failed, then the others aren't far behind. Some cars have individual coil packs on each spark plug. Some cars have a single pack for all plugs and some have coil packs which may control two or more plugs.

To check for a misfire (ignition failure) follow these steps:

(Cold start) (Use a pair of insulated pliers)

1) Start the vehicle

2) When the vehicle starts misfiring, disconnect plug leads or coil pack connections one at a time. If the vehicle idles even more roughly, then that plug or pack should be considered fine.
Replug each connection before disconnecting the next one. Once you disconnect a plug lead or coil pack connection and find no difference in poor engine running, then you have likely found the offending cylinder. Check the spark plug condition, lead and/or coil condition and connections on that cylinder.

3) Replace components as necessary.

Oct 12, 2014 | Cars & Trucks

2 Answers

Why ford explorer jerks off

bad fuel pump replace it

Aug 19, 2014 | 2008 Ford Explorer

1 Answer

Engine runs rough

misfire 3.5L V6
those disconnects, each , will slam the PCM into limphome mode.
you need your own $9 scan tool,
pulling the sensors, only stores DTC codes. that only hide there real ones.
next time you pull a sensor, use the scan tool and reset the PCM.
clearing all codes, then drive and see what fails.
imagine a sick patient in hospital bed and you cutting lines to the person.
you cant fix cars with no scan tool and 100x that , if intermittent.
cant. (i can, but have voltmeters and such that can log data)
running good before, , all cars do that even new. they all run
what counts when its bad.
so connect the scan tool and log the sensors, and see
what DTC pops first. and see all the sensor data.
bank1 OXY sensor 1 heaters is bad. (or wires to it melted)

on some cars , if the heater shorts, it will take out other sensors
here ill look yours up in
the heater runs off 12vdc, and the current is monitored by the PCM.
id fix this first, (after all , its bad, fix it)
P300, is all 6 misfiring, that is most likely bad fueling, too rich or way to lean.
the OXY B1S1 short will short the C436 power bus, and maybe
slam B1 full rich,

C436 runs many other things that need power, so if it shorts.
all bets OFF !! all black-yellow wire power feeds.
it runs PCM pin E1, ,EGR, fuel press.reg.sol. , intake air bypass #1 and 2. and screws up altternator pin1 (96 only)

yah, B1S1 , new, and if wires burnt there , fixed.

Feb 04, 2014 | Acura TL Cars & Trucks

2 Answers

I have a 1999 Silverado 1500 2WD, it misfires @ 2nd and 3rd shift point until it reaches 210 degrees then the misfiring completely goes away. I have given it a complete tune up. Any ideas??

joking they all do/ really,! but yours is outside normal.

the OBD2 DTC codes clear, no P0300s at all, or the like?

cold misfire.
new spark plugs , using OEM type plugs and gapped to factory spec. not to Autozoned spec. they lie.

misfire can be many reasons
even a leaking EGR main valve.
1: low compression any cylinder. (compression gauge)
2: bad spark (look for OBD2 pending P030x)
3: bad fueling, (injector balance tests)

there are tests for each , all are simple.
injector clogged or leaking?

is the fuel old?
try techron fuel additive, (i hate additives) but this one is just
more benzine that is already in all chevron fuel. so is 100% safe.
run that, read bottle for rates.
the misfire is real, it can be found.
the first question, is it all 8 cylinders or just 1.
we can do a spark shunt test to find cylinders that are dead
during the misfire.

Oct 08, 2013 | 1999 Chevrolet Silverado 1500

1 Answer

1993 jeep grand cherokee loses power at operating temp.

ever do a real tuneup this decade
spark parts, and filters. that be first
and make sure the hot engine (sized not stated) is really hot.
180F or more, and holds, it must reach normal spec, temp.
or the ECU brain will not do its job right.
the only clue I have here is skips
skips must mean misfire.
there are over 50 causes of misfire.
bad spark plugs tops the list.
and all spark parts there, cap/rotor,wires set this OLD.
car is old , needs a major tuneup

they to forget all that other stuff, and elaborage
what skips means.
i guess never cold does it skip.

taCH DROPS TO ZERO BUT engine not heard to stall?
if yes, electrical problems or CKP failing?
what does engine do when TACH does that, matters big time.

Mar 07, 2017 | 1993 Jeep Grand Cherokee

1 Answer

Hi I have a 92 model Fiat Uno 4 door i jst did service on it but da car has a miss sort of a fish bite but wen it reaches abt 2000 revs da car runs smooth wot could be da prblm

Sounds like a cylinder misfire to me. There are MANY things that can cause a cylinder misfire. Misfires that occur only at high speeds are usually caused by ignition parts (Spark plugs, wires, coils, etc.) or clogged up EGR ports.

May 20, 2012 | 1994 Fiat Uno

1 Answer

Sticking Valve in #2 Cylinder when cold mostly(misfire condition)

You can't fix this without removing the cylinder head, sorry.

Apr 25, 2012 | 2001 Ford Taurus

1 Answer

Engine codes displayed on OBD tool

You might want to start with spark plugs. I'm not sure if that year has coil on plug ignition, but if it doesn't, spark plug wires are probably in order as well. Some of the O2 sensor faults could be caused by the poor ignition your mis-fires are causing. Sensor 1 is closest to the engine, sensor 2 is further away, on the other side of the Catalytic converter.

May 09, 2017 | BMW 325Ci Cars & Trucks

Not finding what you are looking for?
2003 BMW Z4 Logo

101 people viewed this question

Ask a Question

Usually answered in minutes!

Top BMW Experts

Frankie B

Level 2 Expert

65 Answers

Fred Sops

Level 2 Expert

272 Answers


Level 2 Expert

254 Answers

Are you a BMW Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides