That's a harsh reality that I don't want to accept. I'm not saying you're wrong but the alternative is selling the car for pennies on the dollar because it doesn't run...

 

The PDM is kind of a gimmick... it's not really anything that benefits you, to be completely honest. Any aftermarket system you buy, you're going to have to wire it up... all the same, the PDM really means nothing.

Ugh, I hate to be so frank here, but I agree with IHBD... unless you plan to really teach yourself how to work on cars, this is absolutely not the car for you. We've all been where you are... and I can tell you right now the Holley Sniper is absolutely not the solution you're looking for. It's going to be serious money, and you're going to end up with even more problems, and likely something that will result in the car probably ending up in the junkyard.

Let's say you do spend the money and get the Holley Sniper EFI 2 running. You said your engine has 170k miles on it. How much longer do you think you've got until you spin a bearing and then have to rebuild it? Look... I've spent tons of money... I mean tons on stupid stuff. My user name, 82-T/A is a perfect example. I was 19-20... living in an apartment... I bought a 1982 Pontiac TransAm WS6 from an auction. It was everything you'd expect from a car that had 150k miles on it. It smoked like hell, had absolutely no ignition timing because someone ripped out the Cross Fire Injection and installed a carburetor and intake, but left the computer controlled distributor. I could barely accelerate, but it was enough for me to cruise around town. I spent hundreds of dollars on a set of Hooker Headers, even though the damn thing barely ran.

This is honestly kind of the situation you're in right now... if you've saved money... PLEASE don't spend it on this Holley system. Your car is probably still in really decent shape. I see you're a new user here... only like 8 posts, we can help you figure out what's wrong with your car, and you can do the work YOURSELF... for probably a couple hundred bucks. Take some pictures, let's start a whole new thread about what your car is or is not doing, and let's get your car fixed for a couple hundred...

 

Understood. My vehicle is still at the mechanics, who is still diagnosing the vehicle, which he believes to be the ECM. I'll get it back this Tuesday, and I'll quote reply with a link to the new post.

Thank you for the assistance and support, I do love this car, it's the most fun, easiest to work on vehicle I've ever experienced, my first manual, my first coupe, my first car that I can say I really enjoy. I understand though that it's not realistic or responsible to own. I suppose I'll get it in running order and try and get what I can for it, and put it into something else.

 

Totally get it... I definitely understand.

Just want to give a quick example... you say that the mechanic thinks it's the ECM... I can tell you right now, with the system you have, you literally stick a paper clip in the ALDL under your dash, turn the key to the on position (don't start it), and if the check engine light flashes Code 12 three times... that means your ECM is good. There's nothing else the mechanic needs to know. Most mechanics working in shops today have never had to work on a car with an OBD1 system, or they have no clue about it. We can help with that...

 

Bullshit. NOT IN A 1993 !!! EDIT: Actually, not for any ECM in any year in any GM. Code 12 means "No Reference Pulses Being Received", which there won't be when the engine isn't running, which it isn't when you are checking codes. I'll go one more. With the engine running, and ALDL jumpered it goes into Field Service Mode which indicates closed or open loop, and rich/lean (actually O2 voltage above or below .450) on the SES light. << How does it know which one? By reference pulses. There is no other indication that the engine is running other than reference pulses.

Dude. You have a Fiero, had an F-car and have a 1984 Y-car. Numerous posts in this thread alone reveal that you don't have a clue regarding the nuances of a 92-93 LT1 Corvette. It is very likely that the OP has a bad ECM. Pay attention to the weekly threads on here regarding the driveability problems with the 92-93 (mostly 92, but the 93 is the same POS ECM.) that turn out to be the ECM. These are not the rock-reliable 165 ECM like your Firebird had. 13 model years of C4, the 92-93 is the only one that has several ECM-related threads every week!

 

Sorry IHBD, Code 12 may mean "No Reference Pulses Being Received", but it is absolutely used to determine whether or not the ECM is viable. This is on any OBD1 GM vehicle that you check, it will always flash Code 12, 3 times... it will then flash any OTHER codes (each 3 times), and then it will flash Code 12 three more times. This is written in every OBD1 car manual ever written, and is consistent for almost every single OBD1 vehicle, regardless of whether or not it's a GM. You can refer to this page: Full OBD1 Code List And How To Read Them At Home : "12 System OK ( Diagnosis mode active )"

If you do not get code 12 three times, it means the ECM is fried, or the ECM is unable to communicate. If you have an engineering degree (Mechanical, Computer, Electrical, etc.) or you are just a member of IEEE, you can read about the OBD1 standard here: Design and Development of On-Board Diagnostic (OBD) Device for Cars | IEEE Conference Publication | IEEE Xplore ... this was all done on purpose.

Furthermore, what do you mean by this? "there won't be when the engine isn't running, which it isn't when you are checking codes." ... I hope you're not saying you are supposed to check codes with the engine running, or was this just poorly written? I'm aware that jumpering the OBD1 system, and then starting it, puts it into service mode while running... among other things, this is also when you're supposed to set your timing advance (for cars with a distributor).


Respectfully, my experience doesn't come from 1 Fiero and 1 Transam... I've had 100s of cars. Porsches, Pontiacs, Oldsmobiles, Volkswagens, Volvos, you name it. Look, I realize that when someone new comes on a car message board, especially when they act like they've been here forever, some of the old regulars get upset. I see this on boards where I've been for decades (like RennList, the Samba, Solstice Forum, and Fiero Forum). It's never been at me because I've been there for 10+ years on each of them, but I did always find it a little annoying when I saw people do it to new people trying to help. I apologize IHBD, but you will be making room. I'm going to be here for a while, and my personality is not one to loaf around until the old people get comfortable with me.

By the way, my daughter replaced the fuel filter on our Corvette last week. It was probably the second easiest fuel filter placement I've ever seen in my entire life... as I said, it's a very well-designed vehicle.

 

IHBD is 100% correct here. The Sniper is not the system you want here. IF you are dead set on going with an aftermarket system there are lots of options that will replace the ECU and work with the factory intake and fuel system. Honestly an LS swap would be easier and less costly than a Sniper on an LT1 car in my opinion. Now I'm not recommending an LS swap. I'm just saying it would offer more for less. If you're just trying to get the car running then diagnose and repair. If you're trying to mod the crap out of it and put some real power down then that's when you look into aftermarket ECU's. The only C4 I would recommend the Sniper for would be an 84 to eliminate the Crossfire system. And even then only if you'r also doing a cam swap with it.

 

100% agree... especially because the motor has 170k miles on it. I say get it running again (with the help of this forum, not taking it to a mechanic), and then consider a long-term engine swap if you still want to keep the car long-term.

 

Leave me alone!!

 

Gentlemen, please stick to the topic and leave personalities out of the conversation.

 

Wrong again.
In the 85-91 to set timing you disconnect the "Set Timing Connector". It is a single wire, tan/blk, weatherpac connector. In the C4 Corvette that have distributors that can be 'adjusted' it is in the vicinity of the wiper motor.

 

I'm not wrong, your way is definitely an easier way to do it, and definitely more convenient. That said, in all GM cars with OBD1 and a distributor (non-DIS), you put the ECM in service mode, and you can adjust the timing that way as well.

And just to be clear, when I mean adjust, don't want to be confusing, I mean loosening the distributor hold-down and rotating the distributor. Thanks...

 

New thread started, here's the link:

https://www.corvetteforum.com/forums...post1608788245