I'm having a wierd issue with my ride.
 

Ok so this has been going on and off for a week now and I have yet to figure out the issue. It is random too.. It happened last friday going down the highway where the Tach jumps all over like crazy and pops off 6k. Now here's the funny part my engine is bogging down during this and wanting to stall. Now with that being said I think its the transmission trying to figure out which gear it wants and I know its on its way out (second slips) but its not on acceleration just usual cruising. Some days its fine no issues. Today around 3500 to 4200 it does the same thing sputtering and now backfiring. During that the tach jumps all over from 0-7000. I just did the intake gaskets all the way to the heads so I know there isn't a vacuum leak well I hope there isn't. I'm still losing coolant and now oil is on the tranny. I shift this tranny manually because the overdrive slips up hills and I get tired of the surging.. No codes are thrown so I cannot pin point what the issue is. If this car gives me anymore problems I'm getting close to junking it.... Payed $4,500 for it and invested $2,000 to keep it running so I can get from point A to B. Now I barely feel safe to go 10 miles in it without worrying of it dying on the side of the road...

Well the over driver surging is most likely a torque converter.

I was afraid of you saying that lol...:p but would that cause backfire?

I'm assuming that you may have a head gasket issue if you're losing coolant, the car bogs and backfires and such. Go to autozone and rent a compression tester to see. Also check your oil, look for white smoke from the tailpipe or any signs of overheating. Secondly I would assume that your engine computer is going whacko. Maybe try a junkyard ECM and a dealer programming?

I was thinking that a ECM might fix it but finding an alero that hasn't been stripped around me is hard. I've dabbled with two and the ECM is gone after I get to it. it has 162xxx miles and has overheated twice so warped heads is what is the backfire issue bust as far as the Tach acting goofy I don't want to rule out a ECM. The BCM has a ghost I swear.. Doors don't unlock when put in park even though I set it up to do so. DRL's don't work, the horn for the lock button works when it wants and god help alt acts up.. like I've fixed the alt and other instrument issues but this car doesn't stay fixed lol. I love this car don't get me wrong but everyone keeps telling me its a pos.. I might just drop 20k in the drive train and call it done but I might as well keep it then lol.

Also this is exactly two weeks after intake gaskets. I told my mechanic while your there you might as well do the head gaskets but no I'm just a know it all young kid that doesn't know what he is talking about.. I showed it to him two days after he did the work and its still leaking coolant.. he didn't say much and said it seems to be a head gasket.. I'm like no shit I told you to change it... So $150 in part wasted on my dime.. he builds drag motors you would think he would've dug deeper..

If you told him to do the head gaskets while he had it apart i would not be willing to pay for yet another intake gasket set or the labor for that step

I'm think the crank sensor or it's related wiring might be most of your issue. Would explain your tach going all over the place. Plus with timing / ignition being effected it could cause bogging and backfiring. Iv never seen a head gasket cause backfiring or inconsistent bogging. Not saying you do t have a bad head gasket.

I feel ya. The tach problem is weird. I had something similar happen on a 93 ford probe GT. Same thing tach would jump and motor would act funny. Turned out to be a problem with my alternator.