boost problem

[sydsnot2002]

im sure this has been posted loads of times before but i cant seem to find anything relevant.

 

The engine coughs and stutters at about 4000rpm in 3rd,4th and 5th, any ideas as what it cld be? before i get my novice hands under the bonnet.

 

thanks

[cupradave]

I had a similar problem which turned out to be a faulty MAF

try cleaning it first with some carb cleaner to see if it is that before you go spending money on a new one

what year is your car? is it a classic? if so, have you tried running a diagnostic? and checked for fault codes?

I also took off the boost solenoid and cleaned with carb cleaner and re-fitted, dont forget to clean the asociated pipework connected to it as well

================================

ECU Diagnostics : The ECU can diagnose any fault that may arise due to abnormal signals that are sent to the controller. The ECU Check Engine Light (CEL) will illuminate in the instrument console if there is a problem with any of the computers inputs.  It is possible to find which sensor is faulty by following these steps:<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

· Turn ignition OFF.

· Connect read memory connectors. These are the small black connectors under the steering column above the pedals.

· Turn ignition key to the ON position (Engine OFF)

· Engine Check Light turns on

· Code is indicated by Pulsing light - See below

· If Code is OK Turn ignition OFF disconnect the black connectors

· If CEL returns a number of different pulsing lights then check the ECU code table.

· Turn ignition to the OFF position. Disconnect the black connectors.

· If there is a fault, then check the appropriate sensor.

The ECU codes are displayed as pulses of the CEL.  If CEL goes out there is no fault. 

In Diagnostic Mode – No Fault is indicated by the CEL continuously & evenly flashing on/off (this is also used to indicate the successful completion of an ECU Reset) SEE "OK code" in diagram below.

The long pulses (1.3 Seconds) indicate Tens and the short pulses (0.2 Seconds) indicate ones. Pulses are separated by Short Pauses (0.2 Seconds), multiple codes are separated by a Long Pause (1.8 Seconds) SEE "Trouble codes"  below.

The simplest way for an inexperienced mechanic to retrieve codes is to write the codes down in a sort of Morse Code (dots and dashes), and start a new line when you get a 1.8 Second pause (for NEW code), and then add the actual numbers up after code retrieval is completed.

 

 

Code

ITEM

11

Crankshaft position sensor

12

Starter switch

13

Camshaft position sensor

21

Engine coolant temperature sensor

22

Knock sensor

23

Mass air flow sensor

24

Idle air control solenoid

31

Throttle position sensor

32

Oxygen sensor

33

Vehicle speed sensor 2

35

Purge control solenoid valve

42

Idle switch

44

Wastegate control solenoid valve

45

Pressure sensor – Pressure exchange solenoid valve

51

Neutral position switch

once this is done you can reset the ecu if you want by connecting black and green conectos together turn the key to on position then press accelerator to the floor then halfway up for 2 seconds then start car then travel at a speed of over 5 MPh untill the ok code flashes "DO NOT RAGG THE CAR WHILST RESETTING ECU"  

 

[sydsnot2002]

its a classic 96uk.... cheers for that,, now for a totally newbie question

 What does the boost solenoid look like? [:$]

[cupradave]

 What does the boost solenoid look like? [:$]

it will be on the front side of the drivers side suspension turret, has 3 pipes going to it (see blue circle in pic)

 

[Baz69birds]

its a classic 96uk....

 

Mine coughed & did the same!!

& ive got a '94 classic & it was 1 coil pack (as i have 4) it was best to change them all!!

hope this helps.

[sydsnot2002]

going to have a look at it today, another newbie question, where are the plugs and coil packs located? mine doesnt look anything like the photo..

[Baz69birds]

mine dont look like either,

on top of the engine RED LEADS.... thats 1 top coil pack !!

follow them leads.. to the side of the Side of the ENGINE!! & your coil PACKS should be there.

think thats where mine are!!

[Deano 666]

im sure this has been posted loads of times before but i cant seem to find anything relevant.

 

The engine coughs and stutters at about 4000rpm in 3rd,4th and 5th, any ideas as what it cld be? before i get my novice hands under the bonnet.

 

thanks

before you start to pull things about, it is best to do the fault code read. this will give you a better indication with what is causing the problem. it does sound like the MAF to me. but you can never be 100%. there are many things that can give the same symptons. good luck.