Over boosting

[Eggdrop]

Ok, so my boy just got into a major issue with his s14. He was told that he melted the piston in cylinder 3 cause he was overboosting. He is using a s14 sr and it was rebuilt. He has only been driving it for about 5 months. Does this sound right?

[downshift_sideways]

No of course this doesnt sound right.

Check your wastegate.

[Wei240]

how much boost and for how long?

[Eggdrop]

What could have happened than? the car went nuts. we drove it about a block at like 5k rpms and it caught fire under the hood. then it started to run like crap. now the shop is saying that #3 is gone and that its his fault cause of overboosting. maybe im confused with the complete definition of overboosting, but from what i have seen his car has only twice went past the max for his turbo. it spiked once or twice cause a hose came loose and the gauge showed about 1.3 bar

[Eggdrop]

according to what i have seen his low setting is 10psi. at most i think it went as hih as 1.3bar

[Eggdrop]

bump need help please

[TAMTANIUM]

wow..

hmm....

you said the engine caught on fire under the hood? Ohh noo..

I think the reason for the fire was there was a heavy oil leaking from the engine that lead to a fire. Maybe the valve cover seal went bad? Oil leak somewhere else? That can lead to why the piston melted. Did the shop say you guys spun a bearing or anything like that? Overboosting and overheating = engine failure.

Overboosting: boosting over the limit of your fuel injectors and engine components can hold. I think that's is my definition.

[NemeGuero]

http://www.ka-t.org/overboost.php

[Eggdrop]

there definately was oil around. it also looked as if oil had either came from the valve cover or the turbo itself. they didnt say anything like that. they said that due to the over boosting it happened. issue i have with that is like i said before, it only went high like 2 times. i find it hard to believe that this could have happened cause of that. it wasnt prolonged either, we noticed that it spiked and we stopped the car. the shop did all the work on the car including the rebuild. it never really drove right. for example the turbo on it was bad. they knew that and told my boy to drive with it until he broke in the engine. that was like 3-4 months having that thing in there. then they finally changed it and now this happened. I think they are trying to get themselves out of having to fix the problem that they caused. they are trying to say that this whole thing is his fault and he will need to pay for all the service.

[RR240SX]

Leaking injector caused the fire and lean condition killing the #3 cylinder. It could happen but you should have smelled the gas. 1.3 bar basically 20psi is to much for stock injectors. Running to much boost causes a lean condition that rings don't like. Downshift_Sideways called it , check you wastegate. If the car has a manual boost controller your son may have been driving the car harder than you think. Another senario is that the #3 cylinder was low on compression to start causing it to run poorly from the beginning and finally giving up. It's all guess work at this point.