car is FECKED help

Need technical Q/A then you're in the right place

Moderator: martauto

Post Reply
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 9:53 am

my car just seems to misfire really badly all the time, it only really goes anywhere with my foot right to the floor, but then misfires when it reaches 4000rpm+, anything less than full throttle and it misfires to hell. but it is holding back a lot all the time

this problem has gradually got worse over the last couple of days and i'm quite stumped as to what it is. problem is that i rely on my car so am in desperate need to get it sorted.

anyone any ideas?

its an m40 1.6 just to clarify.

any help or info appreciated thanks.
daveo
E30 Zone Newbie
E30 Zone Newbie
Posts: 60
Joined: Sun Dec 11, 2005 11:00 pm
Location: Chester ,Cheshire

Tue Feb 12, 2008 9:57 am

i would start by checking or changing your spark plugs.

Dave
d6dph
Married to the E30 Zone
Married to the E30 Zone
Posts: 12435
Joined: Sun Aug 14, 2005 11:00 pm
Location: Tiptree. Essex

Tue Feb 12, 2008 10:10 am

Don't the M40 lumps have a problem with the cam wearing and causing it to not rev over 4k? May be worth looking into.

Or the usual suspects of distributor cap or rotor arm.
Image
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 10:17 am

i was thinkin distributor tbh, plugs and leads were new a few month ago but gonna check the plugs after work maybe they need a clean.

cheers

maybe a bent valve or somethin could it be
Templ8e30
E30 Zone Addict
E30 Zone Addict
Posts: 2801
Joined: Mon Jan 10, 2005 11:00 pm
Location: Ashton-under-Lyne, Lancashire

Tue Feb 12, 2008 10:19 am

Check for air leaks around the inlet manifold and throttle body and especially the underside of the black intake hose, any cracks or splits here and it'll run like a bag of shite.

Cheers,

Iain T
Image
2007 Mazda 6 2.0 estate
Political Correctness - A concept based on the idea that its possible to pick up a turd by the clean end !
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 10:38 am

the hose that comes and joins the bottom of the intake hose is cracked and the intake hose that joins the throttle body is cracked but has been ok up till now would it get progressivly worse? i'll need to go to a scrappy and see if i can get new hoses,
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 10:44 am

also the car runs a bit better first thing in the morning but as soon as its heated it gets really bad could this be anything
Chris-W
E30 Zone Team Member
E30 Zone Team Member
Posts: 7219
Joined: Tue May 24, 2005 11:00 pm
Location: South Cheshire
Contact:

Tue Feb 12, 2008 11:05 am

Blue temp sender failing, coupled with existing leaky intake hoses, sounds like to me.
Image
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 11:09 am

anyone got a pic of where this blue temp sensor is as no idea where i'm looking

cheers
ric325i
E30 Zone Squatter
E30 Zone Squatter
Posts: 1961
Joined: Tue Apr 04, 2006 11:00 pm
Location: Gateshead

Tue Feb 12, 2008 11:19 am

blue temp sensor is on top of the thermo housing.

right at the front of the engine just near the injectors there are 2 sensors with wires going into them. one brown and one blue.
very top if the thermo area, very front of engine.

brown is a bugger to take out but the blue aint bad.


also you could just look at the plug for the air flow meter. they can drop off if the metal clip is not in place.
which would mean your car will fire but not fire right.
happen to Gall a few weekends ago, big flames from the back fire :twisted:
Image
Chris-W
E30 Zone Team Member
E30 Zone Team Member
Posts: 7219
Joined: Tue May 24, 2005 11:00 pm
Location: South Cheshire
Contact:

Tue Feb 12, 2008 11:27 am

Sadly not there, Rich. It's in the side of the head underneath the inlet manifold.
Image
Templ8e30
E30 Zone Addict
E30 Zone Addict
Posts: 2801
Joined: Mon Jan 10, 2005 11:00 pm
Location: Ashton-under-Lyne, Lancashire

Tue Feb 12, 2008 12:19 pm

e30mtech wrote:the hose that comes and joins the bottom of the intake hose is cracked and the intake hose that joins the throttle body is cracked but has been ok up till now would it get progressivly worse? i'll need to go to a scrappy and see if i can get new hoses,
These parts are available new from the dealer at a fairly cheap price.

The splits in the intake hose let un-metered air into the engine causing it to run lean. When cold the engine is under cold start enrichment which will mean the engine runs less lean when cold.

As the splits get worse over time the poor running will get worse.

Cheers,

Iain T
Image
2007 Mazda 6 2.0 estate
Political Correctness - A concept based on the idea that its possible to pick up a turd by the clean end !
ric325i
E30 Zone Squatter
E30 Zone Squatter
Posts: 1961
Joined: Tue Apr 04, 2006 11:00 pm
Location: Gateshead

Tue Feb 12, 2008 1:06 pm

Chris-W wrote:Sadly not there, Rich. It's in the side of the head underneath the inlet manifold.
oops :o: i must be getting mixed up. i though the blue and the brown were on the top. maybe im thinking m30?

or maybe im just wrong but good man to correct me nice a quick or the wrong info would be sent out :(
Image
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 1:15 pm

can i rob a temp sensor off my 525 e34 to fit is it the same?
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Tue Feb 12, 2008 9:37 pm

got home had a squint at the car. checked plugs and leads nothin out of the ordinary.

took of the intake hose cleaned the throttle body of any muck then took the top off the air flow meter and messed about with the dial on it. iset it back a few clicks while testing the car in between. finally made a few more adjustments to it and it runs pretty sweet now.

car is a bit lumpy at low revs but when it gets goin its 10 times better now i got some power. gonna adjust it a bit more either way tomorrow till i get the best result as i ran out of daylight today.

seems to have sorted the problem for time being anyway so cheers all, should get a new engine by end of month anyway.
Dr Firefly
E30 Zone Doctor
E30 Zone Doctor
Posts: 1027
Joined: Fri Apr 07, 2006 11:00 pm

Tue Feb 12, 2008 9:44 pm

e30mtech wrote:got home had a squint at the car. checked plugs and leads nothin out of the ordinary.

took of the intake hose cleaned the throttle body of any muck then took the top off the air flow meter and messed about with the dial on it. iset it back a few clicks while testing the car in between. finally made a few more adjustments to it and it runs pretty sweet now.

car is a bit lumpy at low revs but when it gets goin its 10 times better now i got some power. gonna adjust it a bit more either way tomorrow till i get the best result as i ran out of daylight today.

seems to have sorted the problem for time being anyway so cheers all, should get a new engine by end of month anyway.
Not really the way to fix a problem I don't think! It'll just mask the real problem and make it harder to definitively fix, especially as now when you do fix it it might not run right because you've messed about with the AFM. Had similar problems with mine a while back, so I do sympathise with you!
Image
tylerma wrote: you oxymoron, you...
User avatar
e30mtech
E30 Zone Regular
E30 Zone Regular
Posts: 430
Joined: Wed Dec 05, 2007 11:00 pm
Location: glenrothes, fife

Wed Feb 13, 2008 10:52 am

yeah i realise that mate but what can i do i've no cash till end of month so needed a quick fix so it done the job for now.
Post Reply