Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
ron350 wrote:Please post a picture of this possessed motor.
Will do. No time to work on it this past week. We'll try to get some and maybe a video of how it's acting this weekend. No laughing at my elbow patch jobs, the mechanic checked for air leaks all around the throttle body and they work perfectly
95naSTA wrote:If your booster hose coming out of the back of the upper intake keeps flying out, it's not in there correctly. That would cause a vac leak.
Is it supposed to have an O ring or something? It shook loose while on a rough road years ago and we only had it come loose a few times since, but the car ran fine.
Yes, there is an o-ring and 2 tangs that should clip and hold it in place when fully seated in the upper intake manifold.
95 SLE... a keeper. 241k miles. Low and Slow.
97 BMW 528i
98 Infiniti vq35'd i30: 13.3@104mph, 30MPG Hwy (RIP)
02 Jag X-type
03 BMW M5
05 Chevy Cobalt LS
07 Infiniti G35s 6MT (Sold)
07 Ducati Monster S2R 800 with DS1000 swap
83 Yamaha IT175K
72 Yamaha DS7: '74 RD250 swap, JL chambers
95naSTA wrote:If your booster hose coming out of the back of the upper intake keeps flying out, it's not in there correctly. That would cause a vac leak.
Is it supposed to have an O ring or something? It shook loose while on a rough road years ago and we only had it come loose a few times since, but the car ran fine.
Yes, there is an o-ring and 2 tangs that should clip and hold it in place when fully seated in the upper intake manifold.
Well here is the final update. We gave completely up and put it in the shop. They spent four hours on diagnostics! Final verdict...... warped intake manifold .... Don't think we would have ever been able to pin that down. Thanks all of you for your help, with everything we changed this thing is gonna run like a dream when it gets out!
Ultimate sadness! And madness! Idle issues returned as soon as the weather turned warmer. Finally got it back into the shop (a different shop) and the lower manifold had to be addressed as well. Problem is, the upper is still sucking in air at the 'upper plenum gasket'. Their verdict is that the replacement manifold is just cheap cheap and it needs to be redone. Car still won't idle right when the outside temp is over 60° They also can not get a diagnostic reading and Want to replace the PCM! I think the shop before this broke something in the wiring, the diag plug is all loose now. Everything I've read says do not replace the brain without testing it, and I certainly will not pay $700 for them to replace it. Any thoughts are appreciated. Is there anyone out there that has good PCM for a 95? I am about ready to find a parts car. Here's my biggest question though. Would it be downright crazy to put some high heat gasket goo on the area they pointed out as leaking? They sprayed some brake cleaner on it and it started to idle right. I will be going back to the first shop to address why their repair failed but I really don't want to let them work on it again, they didn't even fix my stuck bleeder valve and bled the system from the back lines, so even after a new master cylinder the brakes still feel a touch soft.
I have thought through the craziness. Goo is not a good idea. Do you think a rubber strip like oring material covered in heat tape might be reasonable?
So there's a 99% possibility that the shop doesn't have an OBD1 scan tool with the OBD2 plug that the 94-95s have. I wouldn't replace the PCM unless your car doesn't run. I also find it hard to believe that your new upper intake is warped, causing the leaking at your lower intake.
Did you check all the upper intake bolts to make sure they're snug? It's possible since they 'addressed' your lower intake they just didn't put it back together right.
95 SLE... a keeper. 241k miles. Low and Slow.
97 BMW 528i
98 Infiniti vq35'd i30: 13.3@104mph, 30MPG Hwy (RIP)
02 Jag X-type
03 BMW M5
05 Chevy Cobalt LS
07 Infiniti G35s 6MT (Sold)
07 Ducati Monster S2R 800 with DS1000 swap
83 Yamaha IT175K
72 Yamaha DS7: '74 RD250 swap, JL chambers
Well, after the upper was replaced we started leaking coolant, the new lower has stopped that. The new shop, free of charge, took off the upper twice and redid the gasket trying to stop the air leak with no success. All they can figure is the new upper is faulty and not sitting flush. Our neighbor asked if it was bolted on it the right order, is there a sequence that needs to be followed? I mean, I trust the new shop I took it to. My only complaint was them wanting to replace the PCM, when I KNOW the diag worked before the first shop. There is a master mechanic there that did the diag without codes and he came up with the same two things the last codes pulled which was the maf circuit and crankshaft ps. So, he's good. The pigtail on maf was indeed fried, so it was replaced. And that bad wiring on the cam ps was more than I could get to and both it and the ckps wiring and pigtails were melted up. Oh, two complaints, they would not do the ckps wires without replacing the sensor too because in the initial diag he just touched it and the car died. So I'd say that was the pigtail but I ended up paying for the sensor too, which was just replaced. Ah another totally functional sensor for my collection. And yes they do have and did try to use the obd 1.5. First thing I asked them, lol.
It really is a good shop. The o rings in the quick connect to the fuel lines finally gave out. As we were there with one of the mechanics going over the repairs we noticed it go drip drop and freaked out on it a bit. He had tried to order new ones through their system but could not get them. He walked over to a parts store and bought some out of his own pocket and replaced them. The reason they are so insistent on the PCM is because with being able to pull just one code they can guarantee the fix. I had to argue with them to do the wiring and lower intake. One of the other mechanics hammered out the oil pan so we didn't have to pay for a new one. Oh yeah, the oil pan! Smashed up big time and the first shop didn't even say anything, we were leaking bad, which we were not before that first shop.... I believe the smashing up of the oil pan was totally on me, I did hit a hellaciously big rock :/ I think the first shop screwed us. I don't think this one is trying to. They've even worked out a deal with the parts store to get us a new upper at half the price they can order it at and it still be under guarantee.
