Started Knocking and has no power!!!

[Big Al 389]

Hello new to DSM's but here goes I have a 95 GST auto, I bought it 2 weeks ago it had a bad turbo on it,I replaced it,drove the car about 75 miles and check engine light come on,had it tested said o2 sensor,replaced it drove the car maybe ten miles everything was good.I installed a boost guage and a 1g bov today,when I drove the car about a mile it started to make a knocking sound and lost a bunch of power,also the car has been hard to start and keep running from the time I first got the turbo on it.Can anyone help?thanks...Al

 

[Big Al 389]

I cranked it today and the noise sounds like it's coming from under the valve cover!Pulled it off and everything looks good,nothing worn,broken or loose.Any ideas?Thanks to all...Al

 

[Defiant]

1.) Jumped timing, bent valves
2.) Bad balance shaft bearing.

Best guesses for now.

 

[Big Al 389]

All the timing marks are lined up!Would balance shaft bearings sound as if the knocking is under the valve cover?Someone hear local said it may be a bad cam angle sensor having the injectors and ingnition firing out of time.Does this sound right?....Thanks,Al

 

[Big Al 389]

I also forgot to add that it won't hardly idle til it warms up a minute or two, then it's really rough,and the knocking sound starts at about 1000 rpm's.Sorry...Al

 

[Big Al 389]

Found the problem,spun # 4 rod bearing at low rpms,go figure,may need crank!I'm not real sure yet the crank doesn't feel too bad but you never til she's tore down!...Al

 

[PSI_Tom]

Damn, spun bearings are never fun. Time to get dirty and open the wallet

Typically a new crank and bearing set is your best bet. Since it sounds like you drive a while on the spun bearing, there's a very good chane the big end of the rod was beaten out of roundness and will need to be resized or replaced. Time for "forced upgrades," perhaps?

 

[Big Al 389]

Didn't drive far less than half a mile at low r's,just enough to get off the road.I've drove the thing less than 100 miles since I got it!I'm kinda sorta thinkin maybe JDM forced upgade .......Whos' a reputable dist for the JDM's?....Al

 

[PSI_Tom]

100 miles was probably plenty to do a good amount of damage. If you go with a JDM engine, be sure to buy it from a reputable source and make absolutely sure it's in good condition before you buy. There are lots of horror stories about the condition of JDM "low mileage" engines.

A good rebuild can be pretty cheap, though, depending on what parts you use.

 

[Big Al 389]

I didn't drive it 100 miles knocking only about 1/2 after it started to knock just enough to get out of the road,100 miles total since I got the car.Yeah I got to thinking ,I could probably do a decent build up on for the cost of a JDM.Gonna do some research and see what the better half can be talked into.It's going to be a driver so I'll more than likely stay kinda mild,any ideas anybody.......Al