20mpg m42!

[///M42 sport]

Thats the mileage i've been getting recently. Also experiencing loss of throttle response.

Things I've changed.
Idle control valve
vacuum hoses
Throttle position sensor

Anyone have a spare set of ignition wires and fuel pump sensor I can try? Also what else could be the culprit? thanks.

[3bvert]

still have the throttle body heater adn crap ?
vacum leak ?
pressure regulator ?
compresion ?
crank position sensor ?
if your looking for plug wires, maybe you have a bad coil dropping a cyl

just random thoughts

[ethree]

Air or fuel filter?

[boom-monkey]

Most likely just needs a good tune up.

OT, but I love how people think deleting the throttle body heater improves reliability and power output.

[Adrian_Visser]

how old is the O2 sensor? that would be the first thing i would check

[torqueflight]

Believe it or not, the water temp sensor for the ECU. If the ECU thinks its running cold the mixture is going to be more rich. When I changed the one in my e30 I noticed it ran smoother when it was at running temp. I read about this in a Euro BMW mag.

[///M42 sport]

I replaced the O2 sensor a couple months ago. Spliced a new one in.
Air filter was replaced around the same time
Vacume hoses were replaced 4 summers ago

I did the stomp test and got 1444= no faults.
Idle is great~700

Gonna try the fuel filter and fuel pump relay next, then try a spare set of plug wires.

How do I test the coolant temp sensor? Since I'm completely illterate on electronics.

BTW this all started Suddenly about a month ago which is the wierd thing.

[e30trooper]

I have somewhat the samething with my eta, Running rich dosnt have all the power it did. The batt got d/c a few weeks back after I re connected it the car ran great so im guessing I flashed the ecu and i have a bad o2, I have yet to replace it tho lol

[whiltebeitel]

I replaced the O2 sensor a couple months ago. Spliced a new one in.
Air filter was replaced around the same time
Vacume hoses were replaced 4 summers ago

I did the stomp test and got 1444= no faults.
Idle is great~700

Gonna try the fuel filter and fuel pump relay next, then try a spare set of plug wires.

How do I test the coolant temp sensor? Since I'm completely illterate on electronics.

BTW this all started Suddenly about a month ago which is the wierd thing.

The coolant sensor will vary the resistance (ohms) as the temperature changes. you need to find out what the range is for the m42 temp sensor(s).

[///M42 sport]

^ thanks, I think its on m42club somewhere

also this is how I spliced the wires on the 02 sensor. Is this a pretty good connection? Crimped then shrink wrapped.

[whiltebeitel]

Yep, that wiring should be fine.

[Schnitzer318is]

^yep. no probs there. Put some loom on the whole thing just to keep the weather off everything.

[///M42 sport]

Ok heres a quick breakdown of what happened. (no pun intended)

About 2months ago pulling into parking lot to get sushi, car suddenly idles roughly and dies. I hear a distinct metallic sound inside the intake manifold for a couple secs. I was able to restart it and keep it running only by giving it gas. Towed home that night. Got 1444 on stomp test. Eventually after giving gas and riding idle for couple mins, got car running. Rough idle improved over time till it was pretty stable. but still was getting 20mpg and loss of power!

Vids here.

http://www.youtube.com/watch?v=zXSTeOm2uZE

Asked on forums what most likely happened and what to check.
TPS=replaced
ICV=replaced
vacuum leak=all air hoses 2yrs old. no leaks
02 sensor=couple months old
clogged cat= replaced with newer cat
check AFM, MAF=checked, were freely movable

camshaft sensor= pending
crankshaft sensor=pending
plug wires=pending

coolant sensor= on order
fuel filter=on order
fuel pressure regulator= on order

Then today was listening to cartalk on npr. someone called in about a spark plug blowing out b/c wasn't torqued correctly. I decided to check it mine out since it was easy and I replaced them myself about 4yrs ago. Guess what... it was loose! What was weird was the center elctrode piece had fallen out!!! Not sure if its still in the cylinder or not, but Ive been driving it around like that for 2m's. Think it wouldve worked itself out by now?

I took pics of spark plugs, will upload tonight.

[///M42 sport]

this what I found. NKG, spark plug was loose


the male end of the spark plug came loose and was attached to the plug wire

tip of the spark plug was gone


WTF!

I just drove around a little bit more and its back to its original poor running condition! Could it be plug wires?

[TopOfTheLine89]

definately try plug wires, it was the last thing i tried with a shitty running e30 for a year. As soon as i put them on it was like a had a new motor, responsive, powerful.

get a rotor cap and buttron too probably if this car has one? Or does it just have coils?