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-   -   Starting Problem (https://www.nopistons.com/2nd-generation-specific-17/starting-problem-13026/)

'79rx7 02-28-2003 01:07 AM

Ok, again just in case someone doesn't know I own the '79 with the '86 engine, ecu, and stock efi. Now my problem is that it is very hard to start, especially when it's cold; When it's hot it starts right up. Let me also through in that it might not be your usual problem since it's a bit of a franken-stein car, the fuel pump is wired like a stock 1st gen pump it comes on when the key is on. Pulling the fuse to the pump helps it to start sometimes, but not always, so does holding it floored; the funny thing is if you pull the fuse and hold it floored it will sound like it's going to start at first then nothing if you hold the starter nothing, but if you stop wait floor it again and hit the starter it will start after doing this like 4 times if you're lucky. If not you have to bump start; which sucks, the whole point of the efi would be so that it would start easier in any weather and it has seem to have gotten worse.



Thanks for any ideas



Also should I rewire the fuel pump through the opening circuit and afm like a stock 2nd gen??? Would that fix the problem

HeffSpooled 02-28-2003 01:36 AM

So the fuel pump runs when the key is in the ON position. It almost sounds like it's not running in the START position.




Pulling the fuse to the pump helps it to start sometimes, but not always, so does holding it floored;
This is confusing though, 'cause those sound like "too much fuel" fixes.




Also should I rewire the fuel pump through the opening circuit and afm like a stock 2nd gen??? Would that fix the problem
I don't know about fix, but it would make it a little easier to diagnose I guess.



I wish I were better with electronics. Since the circuit opening relay is connected (powers?) to the ecu, is there a chance that the injectors aren't firing in the START position?

'79rx7 02-28-2003 01:55 AM


This is confusing though, 'cause those sound like "too much fuel" fixes
Exactly it sounds like too much fuel but, then hell I don't know??? I thought the pump shut off in the start position too...




is there a chance that the injectors aren't firing in the START position?
I didn't consider that I'll have to find out, thanks

HeffSpooled 02-28-2003 02:05 AM

I wonder what the absence of the atmospheric pressure sensor would have anything to do with it? I thought I read in another thread that you don't have one.

'79rx7 02-28-2003 02:07 AM

I will get one asap, and see if that helps, I also think I need a new TPS, or readjusted anyways

j9fd3s 02-28-2003 11:00 AM

i dont think the fuel pump running like a 79 would matter. the tps will affect it (a bit), vacuum leaks will also affect it, even tiny little ones. and last your atp sensor, when its unplugged the ecu prolly goes to some default value, if that is different than what you have in reality it will throw things off. the ecu might think you're half way up mount everest



mike

Racer X 02-28-2003 02:20 PM


Originally Posted by HeffSpooled' date='Feb 28 2003, 12:05 AM
I wonder what the absence of the atmospheric pressure sensor would have anything to do with it? I thought I read in another thread that you don't have one.

Thats what I think his problem is too.I still need one myself.I have a friend looking for one right now.'79Rx7 love the sig.So your using the SE fuel tank and lines then?You have a e-mail too. https://www.nopistons.com/forums/pub...IR#>/smile.png

Racer X 03-02-2003 12:06 AM

Any progress?

Racer X 03-03-2003 01:12 PM


Originally Posted by Racer X' date='Mar 1 2003, 10:06 PM
Any progress?

https://www.nopistons.com/forums/pub...R#>/unsure.png

tigger_boi 03-03-2003 04:36 PM

it could be alot of things.... like leaking injectors, fouled plugs, low compression....etc My car has the same problem i have to floor it to start..... i think my injectors are leaking but not for sure.... the local parts store wants $300 can for an injector


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