sluggish

[dramo1]

hey..my car off the line is pretty good wheels spin and takes off ok..my prob is at 40mph or so there is nothing there..makes a lot of noise tech reving up to over 3000 rpms but car is not moving anywhere really..i dont know if its a tranny shifting prob or not..

 

[bossvette]

stick or auto?
are you saying it goes good until about 40 and then it starts to slip the engine revs up but the car doesn't go with it?

 

[dramo1]

automatic..yes theengine goes well till about 40 than it revs but the car does not really go with it..sounds like its going 100 but takes forever from 40 to 60

 

[nyernga]

Sounds like clogged cats.........does it get worse when hot?

Len

 

[bossvette]

sounds like a trans problem simple things first, check the trans fluid. If Ok take it to a trans shop and have it checked out.

 

[dramo1]

just had tranny tune up..i was told if the cats are clogged i would get an error message witch i am not getting..does not seem to get worse when hot

 

[dramo1]

bye the way..u guys are great..cant believe all the help u guys give..awesome

 

[dramo1]

if the cats were clogged would it still take off from a stop the way it does

 

[nyernga]

if the cats were clogged would it still take off from a stop the way it does

It depends on how badly the ceramic inside is. Sometimes they need heat to become dislodged and clog up. Mine would make a rattling sound when cold and performance went downhill after warmup. I would think a tranny slipping would be a smooth yet unproductive engine response. If it TIRES to go but "bogs" down then it's more then likely the cats.

 

[dramo1]

how do i find out if the cats are clogged..a muffler shop??..can i cut out the 2 small pre-cats and leave the big one..will this effect my o2 sensor..how about sound and smell..i have flowmaster cat-back on

 

[nyernga]

how do i find out if the cats are clogged..a muffler shop??..can i cut out the 2 small pre-cats and leave the big one..will this effect my o2 sensor..how about sound and smell..i have flowmaster cat-back on

My pre cats are long gone and I pass emissions each year with just the main cat. Try banging on the cat when cold and see if anything rattles. If so, then it's on the way out.

Len

 

[jmccloud]

Sluggish

I had a car with bad cats; the honeycomb had broken up and turned sideways - also rattled around a lot. At high revs, it was very sluggish and the engine was really trying hard. If on a long upslope so the throttle could be held open longer, the vacuum would get messed up and the air would come out the wrong vents/defrost/etc. Rarely, the car would run well for a few days.
When we removed the exhaust we found the sideways honeycomb and removed it all (beat it out with a long rod). Ran like a champ after that. Replaced the cats to pass emissions (didn't try without them).
I'd say your cats are broken or plugged.

 

[Larry's Yellow Rdstr]

Any good muffler shop can tell if your cats are plugged in a few minutes. Usually a minimal charge. What did your tranny tune consist of? Have a Corvette mechanic drive your car and get his opinion.
Good luck, and let the fun begin.

 

[MBDiagMan]

hey..my car off the line is pretty good wheels spin and takes off ok..my prob is at 40mph or so there is nothing there..makes a lot of noise tech reving up to over 3000 rpms but car is not moving anywhere really..i dont know if its a tranny shifting prob or not..

Can you please clarify? Do the rpm's keep increasing with no acceleration? If so you have slipping clutches and most likely the trans is toast. A good a/t guy can test pressures and tell if it is salvageable with a new governor or something, but if it is slipping, most likely the clutches are gone which will require overhaul.

If the problem is power related, then cats are a possibility among others.

You need to make the determination as to whether the clutches are slipping or it just won't build rpm's. If the rpm's increase without the speed proportionally increasing it is slipping clutches.

Good luck,

 

[dramo1]

Can you please clarify? Do the rpm's keep increasing with no acceleration? If so you have slipping clutches and most likely the trans is toast. A good a/t guy can test pressures and tell if it is salvageable with a new governor or something, but if it is slipping, most likely the clutches are gone which will require overhaul.

If the problem is power related, then cats are a possibility among others.

You need to make the determination as to whether the clutches are slipping or it just won't build rpm's. If the rpm's increase without the speed proportionally increasing it is slipping clutches.

Good luck,

had pre-cats cut out today..no change took it to lee myles tranny is slipping ..he is going to give it real check in the morn..he is telling me anywhere between 1300 and 1700 to rebuild..is that a fair price

 

[bossvette]

the last time I had a 700R4 done (complete R&R) it cost $1100 about 10 years ago. These trans are quite plentiful now and can be picked up much cheaper now I guess it all depends on how much work you are willing to do yourself.

 

[Mad-Mic]

had pre-cats cut out today..no change took it to lee myles tranny is slipping ..he is going to give it real check in the morn..he is telling me anywhere between 1300 and 1700 to rebuild..is that a fair price

thats pretty high. average costs in baltimore for a 700R4 rebuild is 600 bucks less converter. maybe thats with a new converter? if so it should only be 200 more. have it built back to corvette specs with a 2800 stall converter put in and a transgo shift kit.

shop around locally going with this "One" guy he might be thinking your dumb because you own a corvette and will rape you on it. 1700 bucks should be a bad @ss built tranny for high HP not needed for a base model L98 C4.

 

[MBDiagMan]

thats pretty high. average costs in baltimore for a 700R4 rebuild is 600 bucks less converter. maybe thats with a new converter? if so it should only be 200 more. have it built back to corvette specs with a 2800 stall converter put in and a transgo shift kit.

shop around locally going with this "One" guy he might be thinking your dumb because you own a corvette and will rape you on it. 1700 bucks should be a bad @ss built tranny for high HP not needed for a base model L98 C4.

Yes, $600 or $800 sounds more like what I would expect.

Good luck,

 

[dramo1]

fuel injectors

ok..turns out my tranny is ok..cats are not clogged..i posted earlier that the car was sluggish..now it really has now power and is not really reving..i am being told that it could be the fuel injectors..any advice here..price.. what to look for or be aware of..the car sounds like its going 100 but not really going anywhere

 

[Mad-Mic]

ok..turns out my tranny is ok..cats are not clogged..i posted earlier that the car was sluggish..now it really has now power and is not really reving..i am being told that it could be the fuel injectors..any advice here..price.. what to look for or be aware of..the car sounds like its going 100 but not really going anywhere

if it's the injectors pull the plugs and see what color they are they should be a light brown. if they are greyish white they are lean and could cause serious problems. if they are black you are rich. do you have access to a volt meter? if so make another post how to check injectors. i'm not sure so i can't help there because i never had to do this.

when this problem occurs is it high in the rpm range or low. when you say 40-60 mph that could be 1st into 2nd gear but that tells me nothing. is the ses light coming on? could be as simple as a new O2 sensor.