I finished my engine swap this week.
I connected the battery and was about to hit the key. I noticed that the relay ground wires for my fans were not connected to the harness. I picked them up and was about to wire them in, when I dropped then. They touched the computer and grounded. The fan fuse didn't blow or anything. Whould this be enough to kill my computer?
I had not turned the engine over prior to this. I tried and it didn't start. I have fuel at the rail(fp guage) and spark at the plugs. It turnes over like I would expect it to. not real easy but not excessively hard.
I would hate to think that I ruined the computer (and 350 dollars worth of ED Wright programming)
I know that there could be alot of variables I dont think that the harness is one of them It was custom made by fuel injection specialties.
The engine has the mods in my sig. THe cam was installed according the the dots on the sprockets.
Is it safe to spray a little either into the aircleaner and see if it pops? Or will this be haserdous to my engines health?
Anyone have ay Ideas?
Thanks, Kory

 

try to do the trouble code test, try ot retrive codes, it should flash 12 three times, if it dont you fried the ECm, I know htis works on tpi, not sure bout LT!

 

check the main fuse for the ecm? I had a wire come out of the pigtail before and touch my ecm. My car wouldn't start but after a few check it turns out I blew the fuse to my ecm.

 

Thanks for the replys.
I will try them tommorrow and let you know the results. I hope to get it running. That would make this a great Christmas
Kory

 

Won't work on LT1 computer, you need a real code scanner to pull codes from these babies.

 

I reckon that ther be some complicated horse ****, there damn needin a fancy MAchine for them thare toruble codes, heck whe I ws a kid you would just ask the damn thing and it owuld tell you over dinner

 

Ok, you';re saying it's craking, you got spark... if it's cranking you know your VATS is working, if you got spark, you know that your distributor works but you also know that some of it is controlled by the ECM. It must be something else, did you check your fuel pump relay ??? also the oil pressure switch could be deffective or not wired properly.


That's all I can think for now

 

I haddent thought of the oil pressure switch. I am using an autometer oil pressure gauge. I just left the stock plug hanging. The company who made the harness said that that shouldn't be a problem. Maybe he was wrong. (I don't think that he was the normal tech guy) I will have to check this.
Thanks for the replys.
Kory

 

i dont think its the oil pressure switch. the oil pressure switch is an overide for the fuel pump relay. it senses when the oil pressure is built up and if the pump is not running it will send a direct voltage to the pump to start the pump. he said he had fuel at the rails so i dont think this is the problem. If he had no fuel at the rails then i would say it could be the problem.

have you checked for injector pulses yet?

what about the spark tester i told you about?

you could also check the resistance of the coil, the primary side should be .35-1.5 ohms and the secondary should be 5-7 killo-ohms.

another thing is the throttle position sensor. it should read at about .63 or lower. if it is reading above 4 v at closed throttle the computer will think you have the throttle wide open. when the sensor reads above 4 v at start up it goes into clear flood mode. this cuts back the fuel being put into the motor to " clear flooded conditions" the motor would not start in this mode.

something else to check, but probrably not the problem is the engine coolant temp sensor. the computer uses this to calculate fuel needed on start up. im assuming its probrably about 50 degrees or less where you live at this time. so the v reading on the sensor should be 4.25 v or higher. if it is warmer where you live it would be slightly lower than 4.25v.

MAP sensor reading with the engine off should be about 4.8 volts.

MAF can be tested with an osisiloscope if you can get your hands on one. you cant test it very well with a voltmeter cause it sends a frequency signal.

other than that check to make sure all your computer power and grounds are hooked up.

good luck

 

Just a quick update. I checked the injector pulse with a test light.
When I crank the engine over the light blinkes. Not as fast as I would have thought , but it does blink. I am going to go out in the garage in a few minutes and turn the motor over a few times, then I will pull a plug and smell it to see if I am actually getting fuel into the chambers.
I really wish it was summer here. Its slow going on account of The ten degree temp and no heat in the garage.
Kory

 

I cranked it over and then pulled a plug. I have fuel in the cylinders. Now Im confused I have fuel and spark. I assume I have compression. ( I don't know why I wouldn't) fuel ,spark and compression should equal a running motor. am I missing something?
Kory

 

if your getting the fuel and the spark i would suspect that you may have put the cam out of time.

 

it has to be the timming...if you got spark, fuel, and crank the engine has to start ....but like Purplecamaro was saying it can be a ground. Since everything looks good I don't see why it's not starting ... My engine was doing the same thing but I had forgot to plug the optispark ... there's is a chance that your ECM is fried and only some of the function are working ...

 

i have an idea. like the guy before me said, "sorry i didnt see the name" it could be timing. if you put the optispark distributor on yourself it is possible that you could have got the dowl on the end of the cam in the wrong hole on the back of the optispark distributor. I had this happen to me at work one time. If you dont have the dowl on the end of the cam in the right hole then you distributor is way off and it is non adjustable. i would check that. you will have to take it back off. you can tell when you push the distributor down to line it up. but it is hard to explain. if you are not in the right hole, it will feel like it goes totaly flush against to line up the bolts, but if you can wiggle it back and forth you probrably dont have the right hole.

hope this helps. everything else seems to be working. like i said this happened to me once, and for me the car actually started but ran really bad. maybe your in an opposite hole so far off it wont start.

 

THe opti idea seems like a good one. I may be able to get my hands on a scanner this week. If the computer is ok, The opti will be my next step
Thanks for the help ,
I'll keep you posted.
Kory

 

I had a similar problem, turns out that both my MAS and Fuel pump relays were both toast, after replacing them both the engine started right away. Good luck!

 

I just finished taking the opti off and checking to see if it was installed corectly. It seems to be. It goes flush to the block. I tried starting the car. It was the same as before. It cranks but doesn't pop. I hope to get my hands on a scanner in a couple of days.
Kory

 

you are 100% sure that you have spark ???

 

Matt-
I'm sure that I have spark. A friend and I worked on it last night for 3 hours. I don't have injector pulse on all 8 injectors. We then ran each injector hot wire to ground with the ignition on. All 8 wires were hot.
The ecm provides the ground for these right? I think that that the ecm is shot. We checked the 'pulses a bunch of differant times and sometimes half of them worked other times only number 1 worked.
We checked the ground for the harness (we ohmed it ) and it was working properly.
I plan on sending the ecm back to Ed Wright tommorrow for testing.
Do you think that it sounds like the ecm?
Thanks, Kory

 

I made my wring harness as well


VATS 16 pin
|------------------------|
A8| [] [] [] [] [] [] [] []| A1
B8| [] [] [] [] [] [] [] []| B1
|------------------------|

Slot Wire Color Description
A1 Orn Power feed from ECM BAT fuse #4
A2 Pnk Power feed from ECM IGN fuse #5
A3 DK BLU Fuel enable signal
A4 YEL/BLK Starter enable relay control
A5 GRY "Security" indicator lamp control
B5 BLK/WHT Ground
B7 PPL/WHT Ignition key resistor return
B8 WHT/BLK Ignition key resistor feed

| | Top White 10 pin
|K|J|H|G|F|
|A|B|C|D|E|

K is DK GRN and is the coolant temperature feed to instrument cluster.
J is DK GRN/WHT and is fuel pump replay control
H is empty.
G is DK GRN/WHT and is vehicle speed signal.
F is GRY and is fuel pump motor feed.
A is RED and is Alternator feed to instrument cluster.
B is TAN and is oil pressure feed to instrument cluster.
C is BRN and is oil level feed to instrument cluster.
D is empty.
E is empty or if you have a manuel tranny it is the clutch anticipate signal and is GRY.

| | Top Blue 10 pin
|K|J|H|G|F|
|A|B|C|D|E|

K is TAN/BLK and is (Automatic) torque converter clutch control.
J is ORN/BLK and is (Automatic) park/neutral feed from transmission position switch.
NOTE: If this vehicle is manuel the wire would be LT GRN and would be (manuel) backup lamp feed.
H is LT BLU/BLK and is (Automatic) TCC switched power feed.
NOTE: If this vehicle is manuel the would be be BRN and be (manuel) power from turn B/U fuse # 2 to backup switch and would be brown.
G is PNK and power feed from ECM IGN fuse # 5
F is DK GRN/WHT and is A/C request signal
E is DK BLU and is theft deterrent - fuel enable feed.
D is WHT and is techometer signal to instrument cluster.
C is WHT/BLK and is diagnostic request signal.
B is service engine soon indicator feed.
A is empty.

Black Connector 4 pin
|A|B|C|D|
A is PPL and is ignition (crank starter)
B is BLK/WHT Ground
C is ORN Power feed from ECM BAT fuse #4
D is Empty

C100. It connected (on the 93) to the underhood fuse block.
|A|B|C|D|E|
|K|J|H|G|F|
| |
A is PNK and is power feed from injector fuse 9
B is DK GRN/WHT and is A/C compressor relay control
C is DK GRN and is A/C compressor clutch solenoid feed
D is TAN and is serial data signal.
E is BRN and is Air Pump Replay Control.
F is BRN and is power feed from FANS/SOLs Fuse 6
G is PNK and is power feed from ignition fuse 11
H is DK BLU and is secondary coolant fan relay control
J is DK and is primary fan replay control.
K is PNK and is power feed from injector fuse 10.[

check c100 connector near the ecm , connector A, connector K and check all the grounds written above . got to tell you that vats control injectors and starter relay, the motor can be cranking even if the vats not working properly, so check that ...

 

well man? whats the word, get it running yet?

 

I just got the computer back from Ed Wright today. It checked out ok. I plan on getting a scanner tommorrow afternoon and working from there.
I spent about 3 hours testing wiring before I sent the computer away. I only have about half of the injector pulses working all the time. I thought maybe a bad ground, but I can only find one and its ok.
Hopefully I will know more tommorrow.
Kory

 

there should be more than one ground, check to see if there is a ground splice somewhere up further in the wiring. maybe the ground splice in the harness came apart.

just a suggestion. dont know if that would cause your problem.

i forget if that motor has a crank sensor. if it does, i would check the crank sensor. cause either that or the cam sensor would control the injector firing.

 

I was thinking about it the other day and I'm wondering if one of two injectors fusable link could be blown... because there's 2 live wires of the C-100 connector, they both feed 4 injectors.

 

it doesn't have a crank sensor. I think that they went to that in 95. I dont know the cam sensor could be the problem. I don't remember seing it though, do you know where its located? on the front cover i would assume. There is only one ground I found the little schematic that fis sent with the harness. I then called them to double check. They said that there was only one.
Matt-
Where would the fusable links be? that could be a problem?
Thanks, Kory

 

this is what happens when you give up on TPi, now pray to the TPI gods and see if they will let you come back, other wise you will have to give up on being a real gear head, hand in your ***** and buy a ***** with a giant wing. in the mean time I will give you a doller for you LT1 , jki would say your optispark is ****, most early Lt1s had problems with them geting fried by coolent leaking on or in them, i dunno read somhting baout that in super chevy. Anyway good luck

 

I scanned it with a tech 2.
No codes were present.
I then went into the real time screen.
It is getting the low res pulse from the opti. and according to the computer the injectors are getting power.
We checked them with a noid light and it only lit about half of the time.
We unplugged the opti and plugged it back in and got spark on one injector that had never had it before. We took the wire ought and bent the recepticals on it so the fit tighter.
When the injectors weren't working we got an "injector fault" displayed at the bottom of the readout of the scanner.
We got it to pop once.
THen not again. We took the opti apart and checked it out. The cap and rotor looked fine ( They should the motor only had 7k on it) We then went a little deaper. The metal plate behind the optic wheel had some rust spots on it. Does this sound like it could cause a sporatic problem with the injector pulse?
We have checked out everything else. We checked the groundI there three grounded together at one junction point and they all are good)
We checked continuity between the computer and the opti-good.
I don't know what else to check.
What do you guys think?
Thanks, Kory

 

i dont know man, if you have the pulses from the opti-spark you should have injector pulse too. the rust on the opti-sparks metal disk shouldnt be a problem. unless the rust covers some of the holes. the disk isnt magnetic or used to carry electricity. the light sensor on one side senses how many times the light blinks and how long each blink is from when it shines through the holes.

i think i would try a brand new opti-spark though. seems like either that or wiring is messed up. maybe try spraying carb cleaner in the t.b. with the injectors disconnected. at least then you will know its definatly a fuel problem. it should start and run on carb cleaner. just dont do it for too long.

 

Hi Kory… I am not sure what year car your engine is from but this may help you.

I have the service manual for the 1993 Camaro. This book has a section for "no start" conditions and tests that can be performed to eliminate circuits and components. Of course it says to check all the thing your have checked already (Fuses, relays, fuel pressure, ECM, PASS Key, and injectors). It also says to check:

1. EGR Valve: The book says that a "valve sticking open can cause a low air/fuel ration during cranking".

2. MAP Sensor: The book says that a defective MAP sensor may cause a no start or a stall after start. It suggests that you "…Disconnect the sensor. The ECM will use a default value for the sensor. If the condition is corrected and the connections are OK, replace the sensor".

3. The book also say that if the when you check the injectors and the check light blinks dimly, you need to check for shorted injector. You also need to compare injector resistance values. For the 93 engine "all injectors should be within 1.0 ohm of each other and should not be less than 10 ohms at 70 degrees.

The book also has several diagnostic charts. I would send them to you but my scanner is belly-up!

V/R and hope this helps.

m-t

 

Hey guys,
I think that tommorrow the beast will run.
I borrowed a tech 2 and that helped emmencely.
It didn't show any codes but I was able to use the "real time" screen to monitor engine function while cranking. This told me that my opti was functioning properly ( I have both low and high res pulse)
The injectors were working according to the computer, but a test light would not always light. My friend Eddie took the plug out of the opti (the 4 pin plug that goes between the opti and the rest of the harness) We ohmed it and it ohmed fine. He was looking at the plug itself and noticed that it was somewhat elongated. We tweaked it a little making the holes smaller. Then that problem whent away.
Next I removed the injectors and soaked them in carb cleaner overnight. I was putting them back in yesterday afternoon and noticed that my fuel rails (which have -6 fittings welded to the ends and braded hoses with an adjustible reg, instead of the factory lines) were switched. The high pressure larger fuel line was plummed into the regulator and the return line was hooked up on the sender side. Its amazing I was getting anything in the chambers at all. I switched them around and hit the key. It cranked about three times and popped. It backfired and then quit. I thought this was great because this was as close to running as it has been in over a year.
Next Eddie said that maybe the cam was 180 off. so we pulled the timing cover back off. After about 2 hours of thought we now think that it is in correctly but believe that I adjusted the valve lash wrong.
Tommorrow afternoon we plan on resetting the lash and spinning the motor over by hand to check if the cam is indeed in correctly and then reassembling it and hopefully hearing it run.
I'll keep everyone posted.
Thanks for all the help.
Kory

 

Its alive
We readjusted the valve lash and it fired up on the second crank.
I have alot of things to finish before I can actually drive it but at least it runs.
I sure was a great feeling to hear it run after having it apart for over a year. The lt1 hasen't been run in about 5 years
Add me to the list of successful swappers.
Thanks for all the replys and help.
Kory

 

thats great to hear Kory, welcome to the club. glad you got everything worked out, sorry I couldnt be of any help before. but for the last week I was experiencing the same thing you had been. when we put the Hot Cam in, we apparently pushed the dowel pin in too far and it didnt stick out as far as it should have. when I pulled the opti last week to fix an oil leak, I didnt get it seated right. I ran, just not well. when tried to figure out why, we pulled the opti again, seemed fine, reinstalled it, would start again. turns out the pin didnt seat correctly on the back of the opti, it was atleast 20 degrees off. but hey, now I know, pay more attention to it. anyway, good luck with the rest of your swap, keep us updated

 

great to hear man. i was starting to get worried you might give up on her.

good work man

 

Thanks guys.
I think that I'm going to go work on it some more now. I have to go back through my wiring and solder all the connections so they don't come loose when I'm driving around. I hope the snow melt soon so I can see how this motor will tatoo some black marks on my driveway. 350plus rwp and 373s equals
Later, Kory