2G Hard Start

[jperks911]

Hey guys i can not seem to figure out whats causing my hard start. The car will crank and crank and not start. Ive come to learn that most of the time if i jump the timing conectors in the engine bay the car will start. It's not the coolant temp sensor either. It's mostly on cold start up, usually once it's warmed it will start faster. I've been having this issue for quite some time now. Even after having it tuned I still had the issues. Any insight would be greatly appreciated! Thanks

 

[TheDude236]

You might want to post a video so we can also hear any noises it might be making. There is a lot that could be wrong, but a good place to start would be your coil pack I suppose. Maybe you have a bad relay or sensor, really hard to tell.

 

[AWD-Tony]

Let’s see a cold start log. When was tbelt done? Have you checked base timing? Pump gas?

 

[pauleyman]

I agree, do a cold start log. Did something change recently?

 

[jperks911]

Hey guys a little late to the reply but engine blew up again and I finally got the newly built engine installed. Here's a quick update I just figured out yesterday. I wasn't actually jumping the timing connecter. It was the fuel pump test conector that I was jumping. When it's cranking the cars only getting 8volts. If I add 12 volts to that connector when cranking var starts up.

 

[steve]

The fuel pump rewire should have provided a high current feed to the pump. It isolates the MPI relay and check connector from the fuel pump if done correctly.

If your battery voltage is dropping to 8V during cranking I'd clean up all the power and ground connections and look into replacing the battery if it can't handle the load while cranking. You don't say in your profile but with the other mods I wouldn't be surprised if you were using a race battery.

And, as always, Please post a log from when it's having issues.

 

[jperks911]

I've been having the starting issue and for so long that I installed 2 batteries and relocated them to the trunk. I've replaced the batteries 3 or 4 times now

 

[steve]

What it is they say about doing the same thing over and over and expecting different results?

How big is the cable from the back to the front?
How did you connect it to the starter and fuse box?

 

[jperks911]

It's 4 gauge or 6 gauge wire from the engine bay to the trunk, stater wire is the same as factory, and fuse box is the same as factory. I have a power junction post in the engine bay underneath where the battery used to be to connect all the power.

 

[steve]

4 Gauge is marginal at best due to the distance from the engine bay to the hatch. It's fine when your talking the distance from the alternator or starter to the battery in it's normal location. Your typical starter can draw 100A+ while turning the engine over. That will cause a voltage drop at your junction and if you don't have great chassis ground the drop increases.

For reference, I have a 2 gauge wire to the back just for the amps in my stereo and a matching set of ground wires (amp to chassis, firewall to battery, battery to block) That may be overkill but it's how to minimize voltage drops.

Anyway, assuming your power feed to the fuel pump relay comes from the battery and not from your junction you should have good poer to the pump and the power from the MPI fuel pump relay is only used to activate the rewire relay. If the voltage at the check connector in the engine bay is dropping to 8v it may not be enough to activate the rewire relay.

 

[jperks911]

I went through and checked the rewire. Found it wasn't wired correctly. I fixed everything and I'm at 10volts when cranking now

 

[steve]

Good news, has that fixed the problem?