Engine Engine Swap - lots of upgrades, not running quite right

So just an update. I found another TPS at the salvage and used a probe on the pos and neg wire on the TPS instead of using a true ground and I was able to set the voltage just under 1v. I also got the fuel pump installed. I drove it and it pulls pretty well but still feels a little flat but the idle does not hang quite as bad as it was. Right now when I hit the throttle it sounds crisp and jumps but it comes down to around 1200 then after it sits there for a second it drops down to around 1000. Keep in mind this is on the factory tach. I probably need to install an aftermarket tach and see where its really idling at but I can still drop the throttle set screw all the way out to nothing and it still idles. I have looked for vacuum leaks everywhere. I am pretty confident at this point there is not a vacuum leak anywhere but I am wondering how much air still passes through the IAC when its unplugged. I may need to replace mine or clean it if it is not sealing off. But either way its derivable now. I Need to pull the valve covers one more time and adjust the valves. Still sounds like one is ticking pretty good when I fire it up. It goes away after I get solid oil pressure so I probably have one adjusted a little looser than it should be but its fine. I think were just looking at some fine tuning now and I have a feeling if I had a MSD dizzy and ignition box it would probably run a ton better but thats not in the budget just yet.
 
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Did you do the idle reset process? disconnect IAC, adjust throttle stop in/out until you hit desired idle speed. Then adjust tps and leave battery disconnected for twenty minutes?

Also, you do not want to introduce msd ignition parts into this until you sort out issues you already have because you'll gain nothing with using those parts in terms of performance and just add another level of possible failure to your equation
 
Yes, That is how I know it still idles high with the set screw closed and the IAC disconnected. And As I stated I am not putting anything new in the mix. I dont have the money for it now anyway. I have not introduced anything new through this whole thing.
 
Hi Pace,
Still at this I see. I’d just looked at the thread quick, saw IACV, was going to respond with” Any chance that you’ve got a preload set a bit tight on an i or E valve, hanging it open slightly, or a sticky valve”? If one’s hanging, well- that cylinders going to grab air from anywhere it can- it’s not picky- right?
Could run a cylinder balance test, might pick up something, too...
I’m certain this could be tuned out, but you’d only be compensating for an error & that’s not kosher, keep moving forward buddy!:nice:
-John
 
I am going to back them all off and run them all back again to double check them anyway since I have no idea which one is ticking right now. Easy enough to do. If no change I will assume thats not it but it is possible. Going to clean the IAC also. Its more than likely the factory one from 93.
 
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I am going to back them all off and run them all back again to double check them anyway since I have no idea which one is ticking right now. Easy enough to do. If no change I will assume thats not it but it is possible. Going to clean the IAC also. Its more than likely the factory one from 93.


I didn't dig back through the thread but did you see what your vacuum was like at idle?
 
Vacuum is solid. Cant remember what it is right now but last time we checked it was where it should be. I dont have a gauge that I leave on the engine.
 
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Yes, It is in the 15+ range. Just cant remember where exactly. I need to re adjust FP now that I have the new pump it. It is sitting about 38ish with the vacuum unhooked but does not change when I plug in the vacuum so I am guessing it needs adjusted now that the new pump is in.
 
Save your money on the msd stuff, not needed and the box usually causes problems down the road. JMO.

So I wont get better advance curves and stuff out of the MSD? I am use to dealing with older carbureted cars but in the past I have always seen better throttle response and a nicer advance curve from the msd.
 
From what I have seen here on these forums this is my opinion. The stock computer, if it is in good condition is capable of handling everything on a 'bolt on ' engine. Within reason of course. I believe it is not needed. Again JMO.
 
So I pulled the upper intake yesterday, Re ran all the valves (still ticking pretty good so I am thinking possibly I need to re measure and go with longer pushrods but will look at that later). I did not find any other real issues. Gasket looked like it had been sealing well and no other leak points found. I did go through the idle settings again and fuel pressure again to make sure it was good. Weird that I cant get the FP to go above about 38psi even with the brand new fuel pump. The pump is made by Quantum and is listed as a 255LPH Performance pump. I have a BBK FPR and a liquid filled gauge directly on the side of it. I run the set screw down and it maxes at about 38 and no matter how much further in a run it I dont see any higher (current alternator is putting out 11.4v and the new alternator should be here any day. This may be the cause) but it does get to a point that vacuum does not change it but when I back it back out to where it just hits 38 then the vacuum pulls it down to 34 or 35 but not much of a change. I am going to re check the vacuum reading on the intake again but not right now (My neighbors are starting to get pissed at me about the noise). After resetting the idle and setting the TPS to .9 if I tap the throttle it jumps to 2k and does not want to come down for what seems like a very long time.

I needed to drive it today to take my truck wheel to get repaired so I loaded up and ended up having to stop for a second. I loosened up the TPS and took it counter clockwise to what should be lower voltage and it was better. With the clutch in it will come down to about 1200rpm and then sit there for longer than it should and then drop down to 1000rpm. Still does not feel like it has the power it should though. This car is frustrating me very badly. lol.

So to sum it up. I am really no where better off than I was. Something is still acting weird, hanging idle and all that. I am going to order some new mufflers for it to quiet it down (suggestions welcome). Want it to sound better than stock but not obnoxious. I am 47 not 27 so dont need it to rattle buildings anymore but the hanging idle I think is mostly whats pissing off the neighbors. I am also going to try and figure out the pushrod length and just hope the geometry is whats off. I did measure before I put the engine together and I ordered pushrods that were slightly longer than stock but yet when I got them in they were the same length as stock so not sure what happened. They looked ok installed but I still suspect that they are short and I know geometry issues can cause clicking. Otherwise the engine seems solid at least. That is the most I have driven it with the new motor and I need to drive it again this afternoon to pick up the wheel.