Guest F14CRAZY Posted November 24, 2006 Share Posted November 24, 2006 Hey guys. I posted this at Bonneville Club. Something's up with my coupe...Howdy. Pretend I'm dealing with a '95 SSEi, but it's actually the supercharged LN3.The past couple days, it seems its just not making the power it should. It's like the Reatta's being pulled by a Tech 4 or something Sad . I can step it to the floor and its just not pulling like it should. It's not like a low boost issue, but like a smaller motor's been put in, or I'm towing A TON, as in 2k pounds. It's much slower than stock. I'm having to give it a lot more gas for just a little acceleration. The transmission seems to be shifting fine. I'll try to point out what I've tried.-I had a power steering leak which was getting on the belt at the same time. I fixed it, replaced the belt (the longer one that runs the water pump, S/C, A/C) and cleaned the pulleys. I thought maybe the S/C belt was slipping. No change.My AC Delco plugs have about 20k miles on them, maybe a little less. I pulled them all out and they all appear to be the same and look normal. No evidence of an injector stuck open, misfire, etc.Plug wires are about the same age. I removed all of them and checked them out. All are within like 4k-6k ohms.I spun all the serpentine acessories by hand, and all spin freely and without noise.I swapped in a known good ECM while transfering my memcal. No change.I'm running an Accel coil pack. Swapped in with a known good Magnavox. No change.Oil pressure is high/good, no abornmal noises or knocks.No CEL or hidden codes. TPS operation is good and not very old. Crankshaft PS was replaced not too long ago, though I will be visually inspecting it.Put it in neutral while on the freeway and the car coasts freely/normally.Checked the fuel pressure, 38 psi key on, 32 psi or so idle. Which seems to be good as far as I know. Spikes up and settles as it normally does when revved. No gas in the regulator vacuum line. Fuel pump, screen, and filter were replaced about 12k miles ago.Have bought smaller amounts of gas while this has been happening, so I doubt its a bad batch of gas.Starts and idles fine. No backfires, no missing.Seems to rev fine in park, but this may info might not help any.Air intake/filter is reasonably clean. Made a quick run with it off, infact. No change.MAF wires appear to be clean.TPS is fairly new and checks out good in Diagnostic Mode (slowly depressing the gas with the engine off and voltage increases like it should. You know what I mean. No dead spots)Catalytic converter was replaced about 25 miles ago.Seems to lack power everywhere in its RPM range.What do you guys suppose is wrong? Thank you. Link to comment Share on other sites More sharing options...
shoreice Posted November 24, 2006 Share Posted November 24, 2006 Just guessing; did you test the ICM? How 'bout a streached throttle cable or a loose bracket or something? Did you test for full throtle movement to get WOT under load. Hope you find out what's wrong, Kenny Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted November 25, 2006 Share Posted November 25, 2006 I swapped in another good coil pack assembly, no change.I can get to WOT, and I made sure the TPS readings are true in Diagnostic Mode. Nothing wrong there.I'm posting on Bonneville Club. I'm thinking something either in the motor or the tranny crapped out. Even at idle in park/neutrel it "sounds" like its under load, like it's in gear with the brake pedal down. Idle RPMs seem a little slow to me as well. Link to comment Share on other sites More sharing options...
Guest Reatta1 Posted November 25, 2006 Share Posted November 25, 2006 Just guessing here, but, you mentioned changing the cat about 25 miles ago. I'd look at that to see if there is any blockage. All the symptoms of a lot of back pressure. Link to comment Share on other sites More sharing options...
2seater Posted November 25, 2006 Share Posted November 25, 2006 It does sound like a possible backpressure problem, especially since that is the most recent change. Any idea what your engine vacuum reading looks like? Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted November 25, 2006 Share Posted November 25, 2006 Sorry I don't have a vacuum reading. I still need to get around and tackle a boost/vacuum gauge.Anyway, a Bonneville Club member said that a bad cat would only act up at high RPM, but my issue is at all RPM. You guys still think it could be the cat? If so, it's not too bad of a job for me to crawl under and sawzall it off for the time being. Link to comment Share on other sites More sharing options...
luftweg Posted November 25, 2006 Share Posted November 25, 2006 Have you thought about the torque converter possibly being bad? Link to comment Share on other sites More sharing options...
Foop Posted November 25, 2006 Share Posted November 25, 2006 With your left hand reach down under the dash and RELEASE the E brake...... <img src="http://forums.aaca.org/images/graemlins/cool.gif" alt="" /> Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted November 25, 2006 Share Posted November 25, 2006 I'm thinking of the troque converter. Bonneville Club suggested I connect a "scan tool" and observe the torque converter slip. So ok, i will.heh, I don't have my E brake cable connected <img src="http://forums.aaca.org/images/graemlins/tongue.gif" alt="" /> Link to comment Share on other sites More sharing options...
88blue90black Posted November 25, 2006 Share Posted November 25, 2006 Have you ever checked the ttc silonoide.By brother's Century had the same problem. That made a world of difference when he changed it. If you are going to changed the cat, I would suggest CatBack Link to comment Share on other sites More sharing options...
shoreice Posted November 26, 2006 Share Posted November 26, 2006 Did somebody stick a potato in your tail pipe? Link to comment Share on other sites More sharing options...
Guest CL_Reatta Posted November 26, 2006 Share Posted November 26, 2006 How'd you find out???? <img src="http://forums.aaca.org/images/graemlins/tongue.gif" alt="" /> Link to comment Share on other sites More sharing options...
shoreice Posted November 26, 2006 Share Posted November 26, 2006 HEHEHEHE!!! Link to comment Share on other sites More sharing options...
arronhultquist Posted November 26, 2006 Share Posted November 26, 2006 were you asking about the tcc silonoid, I am not entierly sure. I'll have to get back on that. Link to comment Share on other sites More sharing options...
arronhultquist Posted November 26, 2006 Share Posted November 26, 2006 ok I am back. I would unplug it. If your engine rins better, that was the problem. If you wonder where it is at, it is on the front of the tans. near the intake and the cruise control servo. If it continues, I would check you fuel pump or filter or run seafoam through the engine. Link to comment Share on other sites More sharing options...
alexhouston Posted November 26, 2006 Share Posted November 26, 2006 You didn't tell us when it started acting up. Was it after the cat converter change, or did you do the cat converter as a trial fix? If you did, it could be the muffler stopped up. I would consider removing the pipes before the cat converter and running it disconnected. If it runs good, that is the problem. This is many times the case when the mechanics cannot find the poor performance problem. Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted November 26, 2006 Share Posted November 26, 2006 I unplugged the TCC solenoid, no change.The cat change was over a year ago <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" />Like Willren of Bonneville Club was saying. I can build RPMs fine, indicating I don't have an engine issue. The tranny's just holding it back. Link to comment Share on other sites More sharing options...
shoreice Posted November 27, 2006 Share Posted November 27, 2006 Well, we did all wonder how long the tranny would hold up to the supercharger. Hope its an easy fix, Kenny. Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted November 27, 2006 Share Posted November 27, 2006 It lasted 20k miles under boost, ending at 172k miles. I don't think that's bad cuz its been through a lot. Obviously would have lasted longer if it had lower miles, or was rebuilt, or was "performance" rebuilt. I didn't and don't have much faith in 4T60s. Link to comment Share on other sites More sharing options...
Guest crtnrds Posted November 27, 2006 Share Posted November 27, 2006 How can you be sure it's not a boost (or lack of) issue? Link to comment Share on other sites More sharing options...
shoreice Posted November 27, 2006 Share Posted November 27, 2006 I remember some of your comments in prior threads, too bad there is no really good direct replacement. and yes, you did very well with a hi-mile tranny to start with. Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted November 27, 2006 Share Posted November 27, 2006 The boost/bypass control actuator is working just like it should. As Bonneville Club pointed out, I'm building RPM just fine. I could redline it if I wanted to, but still not getting anywhere. I've driven it without boost before, and it is slower, but not nearly this slow.If I decide to stay with the 4T60, the one to have would be an "F-7" from a Cadillac. They're built a little better for V8 power.I'm still tossing stuff around in my head. Thrasher shoudl email me back on if there is a such thing as a 4T65-HD controller for the old ECM Link to comment Share on other sites More sharing options...
Guest imported_Fox W. Posted March 6, 2007 Share Posted March 6, 2007 Will the F-7 or HD versions of the transmission work as a direct replacement on a 89 Reatta? Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted March 6, 2007 Share Posted March 6, 2007 Brian recently asked Ryan about that. It seems the F-7 is actually inferior to our current transaxles. A 4T60E could be used with a standalone controller.The 4T60-E/HD really only has improvements to the differential for the most part, and isn't worth trying to use.I still believe the best solution is the 6 speed manual Link to comment Share on other sites More sharing options...
Guest imported_Fox W. Posted March 7, 2007 Share Posted March 7, 2007 Sounds good, how much $,$$$ do you want to convert mine? <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" /> heh heh. The transmission has always been a scary thing for me because I hear that Buicks in general seem to be known for having 'weak' trannys. So far I have almost 130k and no problems, and its one of the smoothest transmissions i've ever felt. (except sometimes when I put it into reverse, it's always kinda been a bit hard when you first do that, is that normal? Mine has done it since I got it almost 4 years ago. Going into drive however can hardly be felt.) Link to comment Share on other sites More sharing options...
Guest Greg Ross Posted March 7, 2007 Share Posted March 7, 2007 Off-Topic, but;<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> I would consider removing the pipes before the cat converter and running it disconnected </div></div>Had this condition once, the old stock exhaust eroded/ failed right behind the converter. What ever catalyst was in there was sure gone. Oh, car wouldn't run worth a damn. With no back pressure, for whatever reason she went into "Limp Home Mode" Literally had to feather the pedal all the time to keep her running. Happened early New Years Eve about 100 miles from home, reached a friend who called a friend and got him to open up his Muffler Shop for me. Cut out the remains of the cat. and stubbed in straight pipe with a flare on one end and gently applied muffler clamps. Worked much better and got me home!This was pre-S/C, straight stock 3.8L Link to comment Share on other sites More sharing options...
padgett Posted March 7, 2007 Share Posted March 7, 2007 If changing out the trans, why not go to the 4T65E-HD from the later supercharged 3800s ? If it fits a Grand Prix, it should fit a Reatta.http://en.wikipedia.org/wiki/GM_4T65-E_transmission Link to comment Share on other sites More sharing options...
Guest imported_Fox W. Posted March 7, 2007 Share Posted March 7, 2007 Why not indeed! If that would work then great! Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted March 8, 2007 Share Posted March 8, 2007 I would say that, but some smart dudes on Bonneville Club were saying the 4T65 isn't better than the 4T60-E. I didn't research it much though Link to comment Share on other sites More sharing options...
padgett Posted March 8, 2007 Share Posted March 8, 2007 See the Thrasher page - about 2/3 of the way down there is a grey section that shows the difference between the 4T60 and 4T65 spiders. The 4T65 is designed for higher torque.There is a chart on the GN page that indicates little difference between the 4T60E and 4T65E but considerable difference from the 440T4/4T60. Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted March 8, 2007 Share Posted March 8, 2007 I so want out of slushboxes... Link to comment Share on other sites More sharing options...
padgett Posted March 8, 2007 Share Posted March 8, 2007 Back in the day, automatics were heavy and had 2 or 3 speeds (weel the original Hydro had a super granny and four speeds but a fluid coupler). 4 speed Muncie was lots better but took a lot of talent to beat a good 727. Today we have five (4+lockup) and six speed automatics that are worlds better. Think the best and fastest is a good automatic with a paddle shifter. Link to comment Share on other sites More sharing options...
2seater Posted March 9, 2007 Share Posted March 9, 2007 Hard to beat a good moderm auto trans. Power capacity is probably somewhat of a problem in this particular case, but I know the GN guys have experimented with stick trannies and generally have gone slower as a result. These are not high revving and peaky engines. Their strength is a flat torque curve and a boosted engine just enhances that even more than the horsepower. I imagine you have seen the guy on the B'ville forum with the turbo install and a 4T80 transaxle? Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted March 10, 2007 Share Posted March 10, 2007 It is true though. An L67 has a flat torque curve and wouldn't get much out of having more than 4 speeds.The 4T80 project is crazy. May be too big to fit in a Reatta but would be the best automatic choice.What I do prefer though is the more positive connection between me and the vehicle with a manual. It's nice being more involved Link to comment Share on other sites More sharing options...
2seater Posted March 11, 2007 Share Posted March 11, 2007 I understand the urge to "stir your own", and it certainly gives you the control you desire. I don't know if it would make it easier, or more difficult, to tune the hybrid engine you have? Link to comment Share on other sites More sharing options...
Guest F14CRAZY Posted March 11, 2007 Share Posted March 11, 2007 I was wondering the same thing. I asked Ryan about it, and he said the memcal would need to be reprogrammed for idling but otherwise doesn't seem that it would make it harder to tune. Link to comment Share on other sites More sharing options...
Guest Greg Ross Posted March 11, 2007 Share Posted March 11, 2007 When you get to the Tuning stage be prepared for some surprises. It wouldn't seem Ryan has never done manual conversion programming, he throughly messed up my PROM. I believe there are other issues besides "idle" where the programming is concerned. I believe Padgett referred to it at the time as "Anti-Fart". With an automatic it doesn't matter whether the engine drops immediately to idle. To reduce emissions, the ECM holds the idle elevated for a duration so uncombusted fuel/ air does not exit the cylinder.I guess where I came from the 5-Spd. is a driving style. I grew up with manual trannies and like being in touch with the driveline. Personal choice! If I were going racing that would be something entirely different.Imagine my surprise when at speed and you put your foot on the clutch the idle hangs up at about 2000 rpm.Once I'm back on my feet and have some time to tinker I'll be asking Scott Pearson to do some programming/ tuning for me. I think he's got the manual tranny already all figured out. I'd rather go where the experience is, if he'll take it on. Process would be a whole lot easier with him sitting in the passenger seat driving the scan tool! Link to comment Share on other sites More sharing options...
john266 Posted March 13, 2007 Share Posted March 13, 2007 This may be just a suggestion, but it has made worlds of difference in cars Ive seen it done on.Instructions:1. Pull catalytic converter off vehicle.2. Set on driveway.3. Get big metal pole.4. Drive pole through center of catalytic converter.5. Repeat step 4 until nothing is left inside cat.6. Install cat and enjoy extra HP. Link to comment Share on other sites More sharing options...
padgett Posted March 13, 2007 Share Posted March 13, 2007 What Greg was refering to is the "Deceleration Fuel Cut Off" which doesn't. If you suddenly back off the gas, the air shuts off faster than the gas (you would think they could handle that with chronosymplastic programming)and a puff of unburnt hydrocarbons comes out the pipe. This is not good for either emissions or the catalyst.So GM designed the IAC to open up a bit and close slowly (too slowly for most) when you take your foot off the gas. To feel what happens just get up to about 45 on a straight level road. Take you foot off the gas and then shift to neutral. Feel the difference.Part of the problem with Greg's car was that we were doing everything by long distance and slow mail and I really do not have much spare time. The right way would have been to cobble up a "clutch in" switch & program it to defeat the DFCO. It just was not done. Link to comment Share on other sites More sharing options...
Guest Greg Ross Posted March 14, 2007 Share Posted March 14, 2007 I do have the pair of duplicate switches including the vaccuum Cruise disable for the brake pedal, just never got inspired to install them in parallel. Biggest risk is forgetting you're in Cruise Control and putting your foot on the clutch! haven't done it yet!Padgett, for my style of driving she's delightful. Link to comment Share on other sites More sharing options...
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