SR Hard to Start (searched)

[jeff13]

I have a blacktop S13 SR20DET in my 89 coupe that does not want to start on the first few tries. It usually takes four or five cranks on the key for it to finally start. I searched this topic but found nothing useful to fix the problem. Is this just a really hard thing to diagnose? I have a new battery, HKS blowoff valve and intake, high flow fuel pump, stock otherwise. I've had cars with bad starters and this does not sound like a bad starter. A bad starter whirls and sputters. This thing just chugs a few times, I stop turning the key (repeat). Then when it finally decides to start, it'll chug a few more times, 'start up' - idle really slow before it picks up rpm. It feels like it just does not want to 'catch' - if that makes sense. The weather does not matter, but it does not do as much after its been run once (I park for an hour or two its good to go; longer than four hours then the problem is back). Any ideas?

[nismostate]

check timing? tps?

[Silvia007]

I'd replace the water temp sensor for the ecu, not the one for the gauge.

[PhopsonNY]

I had this problem with cold starts and discovered my ECU had not been screwed down tight so the Orange wire as outlined below was not making good contact.

Tightened the ECU down and have had no problems since.

[jeff13]

check timing? tps?

Thanks for the reply, I haven't touched the timing nor do not know how to check it but I will look into it. Throttle position sensor (tps) looks clean, other than that, I don't know if its faulty. I guess it would be pretty obvious when I'm driving if its bad right?

I'd replace the water temp sensor for the ecu, not the one for the gauge.

I'm not sure if the sensor is bad and don't know how to check it but will look into it. Thanks. Can you also advise on how it may affect starting problems? I'm just curious.

I had this proble with cold starts and discovered my ECU had not been screwed down tight so the Orneg wire as outlined below was not making good contact.

Tightened the ECU down and have had no problems since.

This looks pretty promising. I will look into the orange wire going to the dash from the ecu. The link was pretty confusing but I'm pretty sure thats what it is saying right? I hope this is it but I will update this post to let others know how to deal with this seemingly common problem. Thanks for the help guys.

[Silvia007]

The water temp sensor tells your ecu if the engine is cold or hot. Depending on which, it'll add or reduce the amount of fuel to optimize the cars starting ability. When it's not hooked up, you can start your car but once it warms up and you turn it off, you can't restart it till the engine cools down (because your car thinks your engine is cold and is sending the wrong amount of fuel for startup so your engine will just turn and turn like if you were to have no fuel or spark). When it goes bad, it can do what was described or it'll be difficult to start when cold but fine when warm. It uses resistance to determine if the engine is hot or cold so depending on when it's damanged it'll stay at that resistance which in turn tells your ecu what the engine is "supposedly at" sending the wrong amount of fuel which will definately affect starting.

[Silvia007]

Once more thing, if I'm not mistaken, that orange wire is the cold start wire ACC wire that powers your accessories before it actually starts up. When I installed my alarm, I didn't hook that up and it was giving me a really hard time when it was cold starting. Never a problem on a warm summer day but on winter days, it would not start, just cranks away. When hooked up properly, it would enable cold startups. Don't quote me on it though, It's been a while since I hooked up my remote start.

[jeff13]

The water temp sensor tells your ecu if the engine is cold or hot. Depending on which, it'll add or reduce the amount of fuel to optimize the cars starting ability. When it's not hooked up, you can start your car but once it warms up and you turn it off, you can't restart it till the engine cools down (because your car thinks your engine is cold and is sending the wrong amount of fuel for startup so your engine will just turn and turn like if you were to have no fuel or spark). When it goes bad, it can do what was described or it'll be difficult to start when cold but fine when warm. It uses resistance to determine if the engine is hot or cold so depending on when it's damanged it'll stay at that resistance which in turn tells your ecu what the engine is "supposedly at" sending the wrong amount of fuel which will definately affect starting.

Thanks! I never knew . . . I'll be sure to check it out. I think its running a bit rich too, so that could be it. I didn't mention but I don't have remote start. I just sit in my car and look like an *** until my car starts, which I don't mind until old ladies ask me if I need help.

[Silvia007]

Old ladies, hahaha, that's classic, anyway, I used the remote start scenario to describe the use of the orange wire. Your ignition always have used that wire just when I hook up my alarm I didn't know what it was for until a while later. Anyway, good luck, I'd also redo all my ground wiring.

[240sxdominos]

I just got my redtop installed last week and have the exact same problem that you describe. It takes a bunch of tries before it starts and then turns on fine for the next few hours. Other than that the engine runs awesome and I cant wait for more upgrades. Thanks for stealing my question! lol.