Having some minor issues (major issues really!) After I had a couple friends help me do an engine swap on my 89 formula. Went from the original l98 to a bayliner 5.7l 350 from (suprizingly) the same year. The bayliner motor was set up with an external fuel pump which I simply ignored and put the tpi intake on it. Starts right up and dies instantly. Quickly found the culprit being a map sensor (most likely) not being present. I found another map sensor and went to install but the connector is GONE. So there was apparently some butchering going on I didnt know about with my wiring harness while someone was trying to remove ac components and accidentally snipped the wrong connectors. Question is, which portion of the wiring harness to look through and the general routing of the map sensor wires and their color..
Any help is GREATLY appreciated. I cant find the wires anywhere and I know where the map sensor was.. just, I see nothing in the general area and alot has been butchered.

 

No MAP sensor in 89. MAF yes, MAP no.

 

That is weird. The pic i posted on another topic was a before and it does show a map sensor passenger side right above the turbo and the heater duct Aftermarket then? How would I go about hooking up a new map sensor then? My maf is non existant either. Should have one or the other. I know the car was aftermarket enhanced and no longer has the maf sensor.

 

 

So the question now is what would happen if I hook up a new MAF sensor? and how would one go about switching from MAF to MAP since that was apparently done.. This car ran like this and there was never a MAF sensor on the intake any where

 

The car has been modified, how is anyone but the individual who did the modifications going to know how it was modified?

 

True, do you know how to test the wires for which wire goes where on the map sensor connector? I dont even want to try to go back to oem. Alot of hands and alot of rigging has been done and im just not worried about it tbh. I just want the car to run lol

 

Since 1989 has no MAP sensor , and has MAF instead , looking at the 1989 wiring diagrams will naturally not show any MAP wiring since it didn't exist in 1989 . Now , since the 1990 did use MAP , we can only hope that whomever set this up to be a MAP instead of MAF (a common mod when using a turbo) used a 1990 wiring harness and here is the wiring diagram for that , showing the colors of the MAP wiring .

 

There's an awful lot of guessing involved here, and guessing or assuming has been the OP's #1 problem since he started posting on the forum.

I'm not trying to be a big meanie about this, but there comes a time when the last resort is a bit of tough love and brutal honesty. When a person doesn't know the difference between an LS1, L98, or a hole in the ground, handing them the keys to a modified turbocharged project car is probably a recipe for a disaster. We're talking about a car that was assembled without a manual. The electronics and turbo conversion are completely custom. Without knowing HOW the car was modified, specifically, all anyone here can do is guess.

Let me put it this way... What you had to begin with sorta worked, but not really, or you wouldn't have gone hack'n and slash'n and changing the engine. No one documented how the existing system was setup before it was further chopped up during the engine swap. So you are pretty much at ground zero. Starting from scratch. You just need to decide what you need to do to make the engine run. Whether that's going back to stock, or adapting a different engine management, or taking it to a professional, that's your call.

Based on the lack of experience and patience displayed in this series of threads, the best option might be to get a carburetor. Because some people find it a lot easier to work with a carb setup, and maybe that'd be easier than rewiring or replacing an entire wiring harness and sensors and making TPI work with a salvaged boat engine. You have really painted yourself into a corner, you just need to decide what you can handle and take the time to LEARN how it works before you jump in and make the problem worse for yourself.

 

I actually appreciate the honesty. I have worked out 90% of the kinks and can say it will run with the information posted. Usually I hop on here when I have nowhere else to go because knowledge is power. Im alot better equipped than you would think and can do quite alot with this car but there is a lot I dont know. It has been a trying and frustrating experience but im almost fully back to oem just dont have ac and heat sadly. I have taken it to 2 professionals who both told me astronomical prices like 6 grand to repair but led me in the right direction. The engine was free so... as for a carburetor, im good.. I hate carbs. Thank you guys for all the help and sorry for earlier rudeness, wasnt called for.

 

Can you pull the computer out of the dash and determine if it's a MAF, MAP, or other ECM?

If you know which ECM you're running it might help narrow down which sensors should be used. After that, there's the chip in the computer, and how it's programmed. If the cam or other parts aren't fairly close to the engine that the computer is tuned to run, it might not run right at all, even if the correct sensors and wiring are used.

 

Ok , so , , , Supposing lsturbo89 is successful in determining why it starts and only runs for a second till it quits . Supposing he does get it running , won't the boat engine's cam be drastically wrong for a turbocharged engine ? If I recall correctly most boats have their engines set up to turn , what , maybe 3500 to 4000 RPM at most for maximum power while the turbo will be looking to make it's best power at quite a bit higher RPMs ?

At some stage it will come to being a matter of how much power is being left on the table due to the impossibility of tuning for such mix matched components ....

 

The turbo is completely gone. No issues there, lol. the only major difference is the valve covers and the cam being flat tappet as far as i knew, but thtas good to know. Don't do anything stupid with this motor then lol I'm about to pull the ecu out and run the numbers. gimme a min and I'll post

 

1227165 tpi maf 86-89
1227730 tpi sd 90-92
1227727 tpi sd 90-91 corvette weatherproof ecm

 

• 
  

 

The 730 map wiring came out of the loom bye the passenger side injector lead.

 

Ok so 90 to 92.. ecm was replaced right?

 

Yes, the 730 uses 3 connectors one yellow or green.
The 165 was maf and used two ecm connectors small and large black like the 730s.

 

This might seem silly, but what do you mean by loom? I found something interesting that i hope is not the issue.. If that is the loom im going to have to wire up a new map sensor.. because that would be the old wiring.. back behind the passenger side valve cover

 

https://en.m.wikipedia.org/wiki/Cable_harness
Looks like either the harness is either melted or that's old tape residue.

 

That's the HVAC harness. The engine harness drapes over the passenger's inner fender and goes through the kick panel to the ECM.

 

So quick update, I have found 2/3 of the wires for the map sensor the missing one is a ground, Can I just ground it to the body like anything else or will that cause problems? The pin is empty on the ECM connector. Also, the map sensor was installed with wire nuts previously. No wonder it disappeared.
Still have to run the light green wire and see where it ends. I have all day tomorrow to do it but knowing me I'll have it licked by tonight

 

Ps, I also found something else missing. There is no knock sensor installed. Guessing I forgot with the engine swap, Napa has for 50 bucks. at least I have the connectors for that hehe

 

There is a splice off the tps blk wire in the harness around the map location.

 

Thank you. I will have to keep my eyes peeled for it while im tracing that wire. Kinda got sidetracked today though, lol

 

Okay, so dumb question... i dont see why it would but i just want to make sure before i bother trying to start it. This car doesnt have a crankshaft position sensor because of the distributor right? And also what is the difference between an 89 knock sensor and a 91 sensor? Can I install the 89 and have it work with the 90-92 ecm? I need this car by tomorrow and couldnt wait for the 91 to ship in. Napa told me it was a different part number but it looked the same.

 

No crank position sensor 85-89 ks ohm out at 100, 90-92 tpi are 3.9k.

 

Sounds like a bad fit, so go return at napa then huh? Car should still run if timing isnt far off though right?

 

With the wrong ks your ecm night throw a code 43, timing is 6dbtdc with the est tan/blk stripe wire disconnected. Not sure if a 43 would put the ecm into limp home mode or not.

 

Im charging the battery right now. I just hooked up the map sensor and put the ecm back into the dash. I will give it a test run and see if it starts and idles in a minute

 

I started the car. It started right up.. idled to 2k rpm and started climbing.. here we go again. Could it just be a bad splice that i did?

 

With a idle that high I'd look for vacuum leaks and at the iac to make sure it's wired correctly and working when commanded in. You can command it in bye jumping a to b at the aldl.
http://www.iroczone.com/2009/10/clea...rol-iac-valve/

 

Yea most likely the iac. I pulled the plenum apart completely and dunked it (no sensors in) to get rid of carbon and oil buildup from the bad turbo. The pintle was completely coated with carbon and needed cleaning. I cleaned it put it back after the plenum was finished, while cleaning I was following a guide that for some reason told me to take it apart.

 

Quick update, and minor question.. I replaced the iac and found a vacuum leak which fixed the 2k idle problem. Now im having another weird issue. I dont remember ever hearing the intake making a sucking noise that originates from just below the butterflies on the throttle housing.. could it be normal and my car has just never been normal before??? Rofl, seems possible. However the intake seems to be running hot.. the plenum is scalding hot as are valve covers, not sure if this is normal either, valve covers yes but the plenum? They are the same temperature is why i mention them. Only thing left is to put exhaust and correct small issues now.. 9 months of off and on repairing coming to a close? How can this be? I feel an urge to start a thread regarding how I probably could of saved money and bought a new car!! ;P I love the third gen body though..

 

The plenum will get hot. Normal to hear a sucking noise it's a controlled vacuum leak throughout the iac passage.

 

Pretty bad when your car is so screwed up from the start that normal scares you, lmao. Thank you all so much!!! Going to take to a shop and have exhaust put on next week I am lacking a pipe bender and acetylene torch.. and mig welder.. neighbors are starting to complain about the open headers x.x
Total spent on this car thus far:
2x alternators (dont ask..) 200
2 starters (one cracked and was returned) 100
fuel pump 90
fuel pressure regulator & adjustable housing 130
iac 60
misc wires and connectors 50
new engine 1500
Fuel pump relay 30
2060 total.. cosmetic fixes and other repairs like spoiler replacement dash wrapping and reupholstery total around 500.
all in all.. very expensive and frustrating. However I learned alot through the process and cant say I regret it.
I bought this car to do my brother a favor. He kept having issues with it and now im looking at another firebird to tinker with, someone save me! Here I go again..

 

Boat cam = ZZ4 "hot cam". Same part #.. I had to build an engine last summer for my speedboat.

-- Joe