Daewoo Lanos Problems 1999 1.5 - Intermittent Starting probs

[owenwhish86]

Hey there,

I am having problems with my Wifes Daewoo lanos.

Here is what it has done.

When I went to drive it a few nights ago, it ran rough and then stalled just leaving work. Now when turning it over, it would turn over really quickly and then sometimes have a backfire out of the throttle body.

Now I went home and hired a car trailer, and when I got back to the car, I thought I would start it. Well it started and was running perfect, so I drove it on to the trailer and thought, ok maybe just some bad fuel.

So got it home, started it, drove it off the trailer and then turned it off. Went to go start it again and it would not start. Again, just turned over and over at a rapid pace with some light backfiring out of the throttle body.

So I then checked spark, it was good.

Checked fuel from the fuel feed hose and it was coming out at a rapid rate.

Checked compression and I got 140-150 on each Cylinder.

I then started again a few nights later and drove it for about an hour. Put some injector cleaner through it and drive it around again. Took it home and turned it off. Started it and stopped it quite a few times after that and it started great. Not one hiccup when it was driving.

Next morning at 630am, started it, started fine and ran ok. About a minute later dropped down to about 2-3 Cylinders and then died. Turned it over again and got the very fast cranking speed with little backfires.

Does anyone have any Idea what this would be? It seems to work well once it is heated up. When its cold however, it wont run.

Cheers

[Pir0]

I would do a small service on it, plugs, leads, rotor arm dizzy cap. [if it has a distributer] My car was doing this a while back, and it was because of 2 things, something seemed to be blocking the injectors, when we fixed that it ran better but still popped up the trottle body, so we had a look around and figured out it was the fuel pressure regulator that wasn't set properly, it was at either below 2 bar or above 3.5 bar. So, I'm not quite sure what exactly your problem could be other than a fuel/air and/or spark problem.

[Turtle_Wax]

Sticky valves? Try an oil/filter change.

[owenwhish86]

Car usually starts, but will then drop a few cylinders after a minute or two, and stall. It will then not start, only crank over and over, with small backfires out of the throttle body.



If when it drops the cylinder, you keep the revs up until it reaches operating temp, it will then run fine, until the next morning when it all happens again, or after it cools down once again.



I have checked-

- Leads and spark plugs are new

- I have tested to see that the fuel pumps out of fuel filter (can also hear it prime)

- Compression test showed that they all were between 135-150

- I have also tried crimping the return line to see if it was a regulator issue.

- Throttle body and inlet manifold cleaned

[daewoomofo]

i wonder if the ignition coil isnt over heating. have you checked the ign. coil?

[owenwhish86]

It occurs when it is cold, not hot. So I dont see how that would be so?

Runs like a dream when it is at operating temp

[owenwhish86]

Just had a mobile mechanic out, and seems you are on to something. Apparently oil to the top end is not making it, hence things sticking, and a worn out/scratched camshaft.

Oil looks good on the dipstick, but theres no point if its not reaching the vitals

Do you use oil flush, or can you pour some diesel through it before the fresh oil?? Any suggestions to get rid of the sludge?

POS yes. But hey, nothings perfect!! Done a good job the 230,000Kms i have had it.(Only problem beforehand was a hole in the muffler)

[owenwhish86]

Nobody has any ideas?

Tried flushing oil, but no use

[MMamdouh]

usage of flush is good for sludg removal but if it is very sevear then you gotta do it manually (take head off and clean every thing with hands) so you got nothing to lose trying the flush... i'd recommend using a flush product rather than diesel.

MMamdouh

[Turtle_Wax]

Depends how sludged up it is. Personally I would only use an oil flush if the engine has had regular flushes at routine service intervals. Otherwise if it's really sludged up the flush will dislodge it and there's no guarantee it'll come out the drain plug so may cause other problems like blocking vital oilways or something. Sometimes it's best to leave the hardened kak alone and just change the oil / filter. Are you using the correct grade of oil? Depends on your climate but I'd try a 0-30 (or 0-40) as it may flow better around the valves during warm up.

[owenwhish86]

The Oil seems to flow fine (I took rocker cover off to inspect valve movements whilst car was running, and it squirted out quite severely).

I started it tonight, and I have pin pointed it to the 3rd Cylinder, and intermittently the 4th Cylinder also.

Both have spark. I then switched the injectors around with the two good Cylinders and no change, its definately something else.

So I did another compression test, and strangely, the first one i did, it showed 30psi, then the second time I did it, it showed 147psi(what it showed last time).


I will try a thinner oil, but somehow I feel I am at a loss

[lanosport1.5]

I have same problem with my lanos 1.5 and i took it into daewoo mechanics and they told me it was egr valve exhuast, gas, recirculation valve that makes it so wont start very good run off idle and runs fine when warmed up for me its going to be a 600$ fix still havnt got it done yet tho

[owenwhish86]

Hmm, but would that limit it to the 3rd Cyl at times?

I might go get a second hand one and see what it does.

[owenwhish86]

Started it up again....

Ran rough at start, until I gave it a few good revs, and then ran fine afterwards.... THis is so frustrating.