Bought a new exhaust manifold due to the old one breaking apart at the CAT. I put th new exhaust manifold in and followed the instructions of tightning it, criss cross pattern and 15 torque. I started the h3 and right away made sputtering sounds out exhaust and idles rough, also check engine light blinks. I drove it up n down the road and it drives fine until u give it alot of gas then it bogs down/no power. Does anybody have any idea what could be wrong. It ran perf untill replace exhaust manifold. Also i replaced the plugs wires MAF MAP TB crankshaft and camshaft sensors.

 

O2 sensor maybe?

 

Hello and Welcome.

Are you saying you did plugs and replaced the mentioned sensors at the same time as the exhaust manifold install.... or, after as an attempt to correct your problem? If you did it all at once, that was not a good idea as you now have no way knowing which action may be the single problem.

What plugs did you use? What (plug) wires, I5s do not have any?????


For future reference, when you post a question about an H3, it goes in the H3 section, please ask it once, not multiple times in different sections, I deleated all those.

 

I did the spark plugs maf map tb camshaft sensor and crankshaft sensor cuz it woukdnt idle. It turned out to be the crankshaft. Then after i drive it for two weeks theexhaust manifold split in half by the cat. I tgen bought the new exhaust manifold with new o2 sensor bolts and gasket. And now the the h3 is sputtering and has no power up hills and chech light blinks when accelerating.

 

which plugs did you buy?? the I5s are very finnicky about anything other than ACDelco plugs

 

I think there the delco plugs ill have to check in the morning

 

I was thinking the torque wasnt right on the manifold but 15 is the spec

 

A blinking check engine light on acceleration sounds like misfire/detonation. Look for air leaks in the intake tract and at the throttle body. A good throttle body cleaning would be in order if you haven't already. You didn't touch the MAF sensor with your bare hands or use a non-MAF spray on it like carb when you cleaned it, right?

 

Im gonna check for air leaks. And i did clean the tb and no didnt touch anything with my bare hands and i used maf cleaner on maf

 

Using anything except the stock AC Delco plugs?