Losing power, getting it back, losing again

[aleros_eat_rice]

I'm thinking it may be the cat and maybe one other thing, but I will ask here. I didn't see my exact question on the search.

Today on my way to work, my car started losing power. I usually drive around 75mph or so. When I left home, it took off reasonably quick, and up until a certain point on the interstate, it ran fine, at 75-80mph it usually runs about 2000 to 2250 rpms. Today, it suddenly started dropping to about 65, and stayed at 2250 or so.
When I hit the gas, it would bog down, and when I let off a bit, it would smooth out. Then on the exit ramp to work, it got pep back in its step. I floored it and it accelerated like never before. Didn't even hesitate or stumble. Then about 5 miles later, it dropped from 60 to around 25 on a hill. I pulled over and put it in park and floored it, and it started hesitating and wanting to stall, topping out at around 2000 rpms. I was able to limp it to work.
When I stopped, it put off that smell like it was overheating.
Any ideas?
Thanks

[Shiwnath]

Check your MAF.. It may need to be cleaned. That would be where I would start.

[aleros_eat_rice]

I was thinkingabout cleaning that anyway. I'll do that in the a.m.

[Papa Rad17]

cat and dirty maf both sound reasonable. If its getting it when you get on it and running fine then I would think it would be more of a sensor issue somewhere. if was more mechanical you'd probably notice other problems.
just thought- could be a fuel or spark issue. fuel pump or dirty filter maybe, even bad gas. or if plugs or wires are going out it might not be getting a sufficient spark.

[aleros_eat_rice]

Did a tune up a few months ago, usinng AC Delco iridium plugs, premium wires, fuel filter was changed in october, and I'm running 93 gas.

If it were the maf, wouldn't it throw a code?

[Papa Rad17]

Originally Posted by aleros_eat_rice

Did a tune up a few months ago, usinng AC Delco iridium plugs, premium wires, fuel filter was changed in october, and I'm running 93 gas.

If it were the maf, wouldn't it throw a code?

not necessarily. have you tuned to run the higher octain? I know boosted motors and some others require it and will cause problems if you run to low octain. not sure what happens if you go the other way like you are. I could see that being a problem if your not tuned to run it, may have combustion at the wrong time causing things to get out of whack.

[sleepyalero]

Honestly. You should not be running premium. There is no benefit with these cars. And they are not meant to run premium unless you are pushing some high hp numbers.

Mine is tuned to run mid grade gas. If I run premium. Ot basically burns the fuel quicker. And I get no added hp gain or mpg gain....


And you would be suprised. Sometimes sensors dont throw codes.

[aleros_eat_rice]

I was thinking of weaning it down to regular. Go to 89 then after a fill up or two go back to regular. But no, it isn't tuned for 93.

But why would it suddenly fly fast then start to bog down again? If it is the maf, I could get one cheap from rockauto, same as the icm. If its the cat, I might just take out the precat o2s and run it like that until I get a new one. I found a new cat online for like $125.

[Redog]

Did you swap the ICM yet?

[aleros_eat_rice]

Not yet, but I was going to get one on this paycheck. I may just take out a loan tomorrow and pay off with my check.

[a.graham52]

Pull the pre cat 02 sensor and see if u get your power back . That will tell you if it's the cat or if u should keep looking. Ur maf sensor cleaning is pretty cheap but if you ICM is going bad, that could also cause these issues.

[aleros_eat_rice]

Redog already shed some light on that, and I was going to replace it anyway. Work has been rained out a few times lately (concrete), so hours have been short, and haven't had a good enough check to get one.

I did read about the precat, and I was going to try that as well.

But again, why would it suddenly act a whole lot better, only to drop back off a few miles later? Either way, I'm getting a new ICM, just gotta wonder if its that, the cat or maf.

[03glgold]

send some of your rain to western kansas...it will give you time to work and get rid of all the dust blowing around here...two problems solved

I specify western kansas because eastern kansas isn't as dry and my dad is overloaded with work he needs to get done (masonry)

[Redog]

don't take out one of those "payday loans" total ripoff. Some interest rates are as high as 98%

Replace the ICM, and see if the problem goes away. You had another post relating to ICM problems before so it's not like your throwing money at it

[aleros_eat_rice]

I meant so I could get one quicker. Like go to autozone and get one now to keep going for now.

[aleros_eat_rice]

I just started thinking about it. I had a blocked egr passage, and that white sludge had to go somewhere. It probably is a clogged cat because of all of that sludge built up.

I'm going to pull the precat o2s and see if that's it.

[aleros_eat_rice]

It was overheating. Looked in the overflow, and I needed to add water. It still stumbles if I floor it (off the line or moving), but it drove like normal all the way home. It even stayed at about 2250 to 2500 rpms at 75 to 80mph.
I looked around for a leak, and I think its the radiator. Oh well, I already have a replacement for it. I just need to go to autozone to get a new tstat and maybe cts, since it'll be accessible already.

The ICM is getting replaced regardless, and the maf is getting cleaned, but at least it wasn't a bigger issue.

[Papa Rad17]

That will narrow things down at least. When you refill the new radiator don't use just water. 50/50 mix is what I've always put it.

[negolien]

Originally Posted by Papa Rad17

That will narrow things down at least. When you refill the new radiator don't use just water. 50/50 mix is what I've always put it.

People do that still? lol the fact this turned out to be overheating scares me you don't have a temp sensor?

[03glgold]

Originally Posted by negolien

the fact this turned out to be overheating scares me you don't have a temp sensor?

I am somewhat in agreement here...if the 3400 likes to occasionally lose gaskets anyways then overheating won't help, but all you can do is put it back so it doesn't do it anymore and hope for the best