landon suttles Posted January 18, 2018 Share Posted January 18, 2018 i have a 89 buick reatta with the 3.8 3800 motor and the egr valve went out and i replaced it. then it melded the new erg then i tried to block off the egr port and that didn't work. also it has a hard time starting and makes a knocking sound but after it warms up it runs fine. please anything will help the car only has 87,000 miles on it . Link to comment Share on other sites More sharing options...
Ronnie Posted January 18, 2018 Share Posted January 18, 2018 Welcome aboard! Have you replace the melted EGR with another one? Link to comment Share on other sites More sharing options...
SCOTT's 90's Posted January 18, 2018 Share Posted January 18, 2018 What other things might you have done on it like; replaced the ICM, spark plugs and wires etc... Link to comment Share on other sites More sharing options...
Ronnie Posted January 18, 2018 Share Posted January 18, 2018 Also, you should check the onboard diagnostics to see if any trouble codes are set. 1 Link to comment Share on other sites More sharing options...
landon suttles Posted January 18, 2018 Author Share Posted January 18, 2018 (edited) i have changed the icm the wires and spark plugs and the melted egr but it still dont run right is there a wiring diagram foe the tps and mass/air bc i noticed someone put two wires into one bc im the four owner and im trying to get stuff right again to the car also the coil Edited January 18, 2018 by landon suttles (see edit history) Link to comment Share on other sites More sharing options...
landon suttles Posted January 18, 2018 Author Share Posted January 18, 2018 also one more question i want to change the coil from a one whole single peace to a 3 coil pack but i cant seem to fine the plate for it to mount to nor the 3 coil pack Link to comment Share on other sites More sharing options...
KDirk Posted January 18, 2018 Share Posted January 18, 2018 (edited) You certain there isn't an obstruction somewhere in the exhaust (perhaps a collapsed catalytic converter)? That would usually take out the EGR (or at least set an error) due to exhaust back pressure. Would also cause it to bog out under any kind of load above idle. The Delco ignition setup with mount and hardware can be had complete from most 1991-93 GM vehicles with the 3800, some as late as 95, assuming you have a yard nearby to source one from. New parts may still be available from a dealer but will be much more costly, naturally. The coil packs and module can be bought new at almost any auto parts store and are sold individually as replacements. Again, better to get a used working one or you'll drop over $400 getting the needed parts new. Edited January 18, 2018 by KDirk (see edit history) Link to comment Share on other sites More sharing options...
landon suttles Posted January 18, 2018 Author Share Posted January 18, 2018 but i also put like a metal plate where the rgr was and that didnt even work but the egr hose that comes out the back goes in the exhaust manifold. but before this prob. i would have to let the motor warm up about 15 min before i could drive it bc it would fire on all cylinders. and the diagnostic text wont even tell me Link to comment Share on other sites More sharing options...
SCOTT's 90's Posted January 18, 2018 Share Posted January 18, 2018 I know on the 90's a mounting plate for the ICM is not required only the coils and module, but not sure about the 89 maybe someone else can confirm it. Link to comment Share on other sites More sharing options...
landon suttles Posted January 18, 2018 Author Share Posted January 18, 2018 because i just heard that the 3 coil pack pushes out more power and not a much lag time Link to comment Share on other sites More sharing options...
KDirk Posted January 18, 2018 Share Posted January 18, 2018 88-90 all had the identical Magnavox ignition system with a "single" coil pack that contained all three coils as one unit. This setup mounts similarly but not 100% identical to the Delco design that superceded it in 91. The Magnavox module is its own mount and doesn't need the adapter plate. The Delco module requires an aluminum adapter plate and 3 special square flush head bolts/lock nuts to take the place of the integral mounting studs on the Magnavox module. The Delco module and the three individual coil packs are held to the mount plate by long metric bolts that install through the coil packs and thread into the plate beneath the module. 91 was the first year for this design (at least on the Reatta). It was used henceforth on most NA 3800 (pre-series one) equipped GM cars through 1995. Some models started getting incremental changes in 94, by 96 it was different enough to no longer be a direct swap to a Reatta AFAIK. EGR cannot be removed on the 88-90 3800 without setting codes (or reworking the ECM program and other mods). The 91 version has no EGR valve but is an updated version of the 3800 engine. Link to comment Share on other sites More sharing options...
landon suttles Posted January 18, 2018 Author Share Posted January 18, 2018 yes it dose send a code but thats if i unplug it but if i plug it in then no Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 39 minutes ago, KDirk said: Again, better to get a used working one or you'll drop over $400 getting the needed parts new. My complete setup was $170 new. 3 coils, ICM, Bracket. Link to comment Share on other sites More sharing options...
SCOTT's 90's Posted January 18, 2018 Share Posted January 18, 2018 17 minutes ago, landon suttles said: because i just heard that the 3 coil pack pushes out more power and not a much lag time If you are referring to Padgett's tutorial on Magnavox vs AC Delco ICM (http://www.reattaowner.com/roj/repair-information/common-problems-a-solutions/replacing-magnavox-ignition-with-delco) then there is not much difference at least you won't be able to tell unless you hook both applications up to a Dyno and compare the two. "So, why do some racers bother to switch ignition systems? It’s a little known secret, but we’re in a generous mood - the Delco coils have lower inductance (approx. 3.5 mH) than the Magnavox (approx. 8mH), and provide slightly more energy. Primary winding resistance of the Magnavox unit is 0.7 ohm vs. 0.34 for Delco. Magnavox current limit is 6.7 amps with a 3.5 msec risetime vs. 9 amps @ 3 msec for Delco. This translates to a risetime energy of 8.58 mJ for Magnavox and 9.87 mJ for Delco. The Magnavox current limit power is 65 watts times current limit duration, while the Delco current limit power is 102 watts times current limit duration. Is this slight energy increase significant? Probably not, but every little bit helps." 1 Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 (edited) 40 minutes ago, KDirk said: 3 special square flush head bolts/lock nuts to take the place of the integral mounting studs on the Magnavox module Nothing special about beveled machine screws at Lowes or Home Depot. (Stove bolts) Edited January 18, 2018 by 89RedDarkGrey (see edit history) Link to comment Share on other sites More sharing options...
landon suttles Posted January 18, 2018 Author Share Posted January 18, 2018 did they try to put a 350 turn port in a reatta Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 That would've been nice- Olds had a beautiful 350-R like my '77 Cutlass. M4M Rochester- it would haul. No, no RWD Reatta. Link to comment Share on other sites More sharing options...
Ronnie Posted January 18, 2018 Share Posted January 18, 2018 To find your problem I think you should get back to the basics. Ask yourself these questions. If you can give us the answers it would help us diagnose your problem. What is the fuel pressure? Have you checked closely to be sure there are no crossed spark plug wires? Does the problem occur just after the engine reaches 160 degrees? Does the problem go away when you unplug the MAF sensor? Does the problem go away if you unplug the O2 sensor? 2 Link to comment Share on other sites More sharing options...
KDirk Posted January 18, 2018 Share Posted January 18, 2018 (edited) 89RDG, surprised you could put it all together for that money. I based my estimate on Delco ICM and coils, dealer ordered plate and bolts. Prces may have come down as well since I first looked at it about 6 years ago. I'm sure aftermarket was less anyway, by at least a bit. There are other bolts one could use (modification or grinding needed in some cases) but i decided to keep it simple and get factory parts. Really, given the reliability of the Delco setup I had no problem putting used parts on my 88's when I did the conversion. Cost me about $50 for the bracket, ICM hardware and coils from a salvage yard, I think Ronnie also raises good points on troubleshooting. Spark plug wires especially, be mindful of the order. Very easy to mix up. Also, the factory service manual reverses the even and odd bank in the tuneup section. If you followed the book, you got it wrong. I speak from experience. Edited January 18, 2018 by KDirk (see edit history) 1 Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 Dealer OEM is going to be a ridiculous price. Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 This could be a vacuum leak. 1 Link to comment Share on other sites More sharing options...
2seater Posted January 18, 2018 Share Posted January 18, 2018 I have having a bit of a hard time following what the OP has going on but I certainly concur with starting from scratch as suggested. What I gleaned from the posts is the diagnostics either don't work or show no codes? There was an attempt to block off the EGR but that either didn't work or has now been replaced. There is some suspect wiring in the area of the MAF or TPS. Before the EGR work, the engine had to be warmed up before being able to drive away. Link to comment Share on other sites More sharing options...
retiredmechanic74 Posted January 18, 2018 Share Posted January 18, 2018 Melting the EGR is a sure sign of to much back pressure. I would suggest to loosen the exhaust at the manifold enough to allow the exhaust to escape but not enough for the pipe to drop off (use longer bolts) then drive the car and see if it runs OK If it does then the exhaust is plugged. I bought a car once ( I think it was a Ford wagon) anyway It had the same symptom you describe. After that test I found that mice had gone up the tail pipe and made a nest. 2 Link to comment Share on other sites More sharing options...
2seater Posted January 18, 2018 Share Posted January 18, 2018 You can also pull the O2 sensor from the rear manifold if backpressure is a problem. Is it possible the IAC is stuck so it cannot advance the idle when cold? Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 A vacuum leak would cause the O2 sensor to go rich. A large enough leak would act like a choke, causing a large enough enrichment to dramatically raise exhaust temps. Warming the engine slightly closes the leak- but give it throttle- and it falls on it's face lean. The closest Data PIDS a Reatta can show you on board to ST/LT fuel trims is O2 Cross Counts (ED18), Fuel Integrator (ED19), BLM (ED20). We need some data- or we're shootin in the dark here. Easiest and safest way to search for a vacuum leak- get a squirt/mist bottle of water, engine running, squirt around the intake/block interfaces, EGR, EGR adapter, throttle body, PCV. When the engine stumbles- there you go. 1 Link to comment Share on other sites More sharing options...
padgett Posted January 18, 2018 Share Posted January 18, 2018 errr always thought that too lean was what made pipes glow. Keep in mind that when I wrote the Magnavox vs Delco was over a decade ago and parts in yards were plentiful. I was paying $40 for a complete set. Sounds like the gentleman has a thoroughly confused 3800 and who nose what parts. Personally never heard of a melted EGR & how does removing the O2 sensor help anything ? Strongly suspect there are codes which may be displayed on the CRT Link to comment Share on other sites More sharing options...
2seater Posted January 18, 2018 Share Posted January 18, 2018 27 minutes ago, padgett said: errr always thought that too lean was what made pipes glow. Keep in mind that when I wrote the Magnavox vs Delco was over a decade ago and parts in yards were plentiful. I was paying $40 for a complete set. Sounds like the gentleman has a thoroughly confused 3800 and who nose what parts. Personally never heard of a melted EGR & how does removing the O2 sensor help anything ? Strongly suspect there are codes which may be displayed on the CRT Late ignition timing will heat up the exhaust too. The comment about removing the O2 was as an exhaust backpressure check, that's where they put a gauge to actually measure it, but just pulling it would answer the plugged exhaust as the cause of not running. I agree that we have bits and pieces but not a coherent description of what's going on. Link to comment Share on other sites More sharing options...
89RedDarkGrey Posted January 18, 2018 Share Posted January 18, 2018 32 minutes ago, padgett said: errr always thought that too lean was what made pipes glow. Sorry about that one- I'm wrong. I was just envisioning a rich mix would be burning stuff. I totally forgot about extra fuel actually "cooling" though evaporation. Link to comment Share on other sites More sharing options...
Ronnie Posted January 19, 2018 Share Posted January 19, 2018 54 minutes ago, padgett said: Strongly suspect there are codes which may be displayed on the CRT 22 minutes ago, 2seater said: I agree that we have bits and pieces but not a coherent description of what's going on. I tried to ask a few simple questions, including one about codes, to try and get enough information to figure out his problem. I don't think they were answered. Maybe he will come back and we will learn more... Link to comment Share on other sites More sharing options...
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