weird cold start problem

[xx503boyxx]

ok so my 90 talon dosent want to start after its bee sitting overnight. after checking the obvious i found out my pump is working but my injectors are not. So i replaced my injectors and still didn't turn on. I put a bit of gas in each cylinder and started up ruff but got it to idle nice after steping on the gas petal a few times. I let it run for 5 mins turned the engine off, the attempted to star it again and it started right up .and idled good and drove good the rest of the day.So what u guys think is the problem so far im thinking temp sensor.

 

[GRAVEDIGGER]

That does sound like a temp sensor That would definitely be a good place to start.

 

[luv2rallye]

Check possibilty of leaking FPR.

 

[HeLzKaos]

i had a problem almost just like urs. where i would let the car sit for a while and it didnt want to crank right up. i had to start cranking then let off and crank again but this time pumping the gas and it started up. it had a little ruff idle till i gave it some gas. i would cut it off and it would start right up but if i was at work it would do the same thing. i did find out that my fuel pump was going bad so i replaced it and put a new fuel filter on and now it starts right up no problems. u might want to look at the fuel pump and fuel filter and make sure u are getting the right pressure. hope that helps

 

[Boosted_Jedi]

Sooooooo... I'm guessing it WAS the temp sensor? I'm having the same damn issue

 

[PlanZero]

If you're replacing the temp sensor it's a good idea to replace the sensor connector as well.

 

[DSM1G90]

From experience here: Same issue and getting stuck in parking lots with a stalled motor.

Replaced Temp Sensor since I had an occasional CEL at times pointing to this issue.

Replaced sensor. for less than twenty bucks from NAPA.

Issue and embarrassment solved.

 

[Boosted_Jedi]

If you're replacing the temp sensor it's a good idea to replace the sensor connector as well.

I purchased the sensor today. The plug to it does look pretty beat up and the wires are hacked up, so I will be working on that aswell. Thanks

From experience here: Same issue and getting stuck in parking lots with a stalled motor.

Replaced Temp Sensor since I had an occasional CEL at times pointing to this issue.

Replaced sensor. for less than twenty bucks from NAPA.

Issue and embarrassment solved.

I am just hoping the problem IS the sensor. Got mine for $20 with tax. I will be updating the results tomorrow. I'm just not looking forward to replacing the fuel pump if it's not the temp sensor.

 

[DSM1G90]

Could also be ECU, but with mine, the ECU, being a reman, is only two years old thus I knew it wasn't an ECU problem.

Now, you mentioned a hacked wires to the plug: if those two wires touch each other with key on, this will blow out the section of the ECU that contains the driver that runs this sensor .. making it an ECU replacement or repair.

I'd head out to a yard, find some busted up DSM's and cut off a plug with attached wires and replace the bad with the good. But, if you know soldering, solder the splices together with shrink tube over the splices instead of twisting wires together and covering with vinyl elec tape.

 

[Boosted_Jedi]

Could also be ECU, but with mine, the ECU, being a reman, is only two years old thus I knew it wasn't an ECU problem.

Now, you mentioned a hacked wires to the plug: if those two wires touch each other with key on, this will blow out the section of the ECU that contains the driver that runs this sensor .. making it an ECU replacement or repair.

I'd head out to a yard, find some busted up DSM's and cut off a plug with attached wires and replace the bad with the good. But, if you know soldering, solder the splices together with shrink tube over the splices instead of twisting wires together and covering with vinyl elec tape.

Well... I replaced the temp sensor and the same issue... Cranks all day but doesnt start. From time to time it tris to fire up but no go. I started it with some starting fluid and let it idle for a while. I shut off the engine and strated it again with no problems. An hour later I went to start it and it struggled a bit but fired up. After two hours later it just wouldn't start. I fixed the spliced connection and made a better one with the proper components and shrink wrapped it. It wouldn't start still so now I am working on fixing some connections on the maf plug that were all hacked up. Next after that is fixing some more hacked wires on the ecu harness (done by previous owner) and checking to see if that fixes the problem. If not, I will be replacing the fuel filter and pump. Thanks for your help.

From experience here: Same issue and getting stuck in parking lots with a stalled motor.

Replaced Temp Sensor since I had an occasional CEL at times pointing to this issue.

Replaced sensor. for less than twenty bucks from NAPA.

Issue and embarrassment solved.

I also have a CEL but dont know how to check it...

 

[Dsmkauai]

From the sounds of your first post I would look at the cam sensor also as it supplies the ecu with fuel injection timing. Check out the wires and also check the sensors to see if they are within oem spec. But it also Sounds like maybe the fuel pump is getting weak. Or you have a small leak that's not allowing the system to stay pressurized like it should. I had a similar issue one time with a customers 2g and it ended up being a bad oring at the fuel pump where the little top hat thing goes. This little ripped oring would allow the fuel system pressure to leak down fast and then caused a hard start and long cranking. Could also be a bad fpr and your not getting the correct fuel pressure to get the car started. Seems like your going in the direction and fixing things along the way. Seems like with the way the p.o. Left the car you might want to go thru a detailed Pm's list before having to much fun with it ! How many miles on the car? When was the timing belt and components changed last?

 

[DSM1G90]

Code 21: Coolant Temp Sensor - Two long beeps and one short beep - music to our ears.

I also have a CEL but dont know how to check it...

Our favorite place to go to and for all DSM owners to bookmark:

ECU Code Checking

 

[Boosted_Jedi]

From the sounds of your first post I would look at the cam sensor also as it supplies the ecu with fuel injection timing. Check out the wires and also check the sensors to see if they are within oem spec. But it also Sounds like maybe the fuel pump is getting weak. Or you have a small leak that's not allowing the system to stay pressurized like it should. I had a similar issue one time with a customers 2g and it ended up being a bad oring at the fuel pump where the little top hat thing goes. This little ripped oring would allow the fuel system pressure to leak down fast and then caused a hard start and long cranking. Could also be a bad fpr and your not getting the correct fuel pressure to get the car started. Seems like your going in the direction and fixing things along the way. Seems like with the way the p.o. Left the car you might want to go thru a detailed Pm's list before having to much fun with it ! How many miles on the car? When was the timing belt and components changed last?

Cam sensor is dead center, I don't know how to mess with it. I am tryin to get everything up to date with the car. It's a 1990 ecelipse GSX with 14X,XXX 5 spd. Ive had the car since 2012. Don't know when the timing belt was done. I HAD previously read about the oring issues before, so I think it could also be that? Where can i get one that will fit? Or should I just get a pack of random orings at like harbor freight and see which one fits? Or just switch out the fuel pump? Thanks!

Code 21: Coolant Temp Sensor - Two long beeps and one short beep - music to our ears.

Our favorite place to go to and for all DSM owners to bookmark:

ECU Code Checking

Ahhhh dude awesome link, I'll be checking this out tomorrow when it's not so damn cold outside

 

[DSM1G90]

Inside the fuel pump is a check valve to keep the rail pressurized and this check valve will start to go and not hold pressure in the rail...and along with a cracked "O"-ring.

One can pull off the timing belt upper cover off and do a visual inspection on the belt to see if there are any cracks, esp inbetween the teeth of the belt, fabric showing wear and similar signs of general wear.

 

[Boosted_Jedi]

Inside the fuel pump is a check valve to keep the rail pressurized and this check valve will start to go and not hold pressure in the rail...and along with a cracked "O"-ring.

One can pull off the timing belt upper cover off and do a visual inspection on the belt to see if there are any cracks, esp inbetween the teeth of the belt, fabric showing wear and similar signs of general wear.

Timing belt looks almost new. The fuel pump is probable from the sesame street era though.

 

[pauleyman]

Fuel pressure can leak down from several areas. If you want to diagnose a few are easy to check or at least find out if fuel pressure is an issue at cold startup.
1. Fire the fuel pump manually before you start the car cold. Unless you've got a leak that's so bad you should at least have adequate fuel pressure at startup this way without cranking to get fuel pressure up. Keep in mind injectors are firing during cranking so if they have little fuel (doesn't ignite possibly) that fuel sits in the cylinder. I've seen this cause stumbling etc at first startup that clears up after 5 or 10 sec.
2. take out the spark plugs before you crank the motor. Smell each cylinder. If any smell like gas you've likely got a leaky injector This can cause the symptoms above and possibly more as one or more cylinders are flooded at startup. Same sputtering startup symptoms until everything evens out.

If the car starts up easily and smoothly after you manually fire the fuel pump I'd say you can likely rule out leaky injectors. That leaves fuel pressure regulator and fuel pump check valve and oring. I've seen many fuel pump orings leak. If you are getting symptoms after a fuel pump install it stands to reason this is a very likely culprit. Easy to change and rule out before you start throwing parts at the car.

Diagnosing the fuel pump itself or the regulator would likely require some well placed gauges. Might be easier to just replace these parts if they are suspect. If you already have a fuel pressure gauge and the pressure does not immediately drop you could pinch off the return line at shutdown. The only place for fuel to go if the line is pinched off is through an injector or back through the fuel pump.

 

[luv2rallye]

^+1. Sounds like fuel pressure is not being maintained at the rail. It should stay there for days. Check for leaky fuel pressure regulator or fuel pump check valve.

 

[DSM1G90]

There is small connector in the harness along the firewall past the ECU ground connector.

This leads directly to the fuel pump where one can attach a 18g wire to it and touch the positive post to the battery.

This runs the pump and if you squeeze the fuel line going into the rail, you can feel pressure build up when you touch the battery.

 

[Boosted_Jedi]

There is small connector in the harness along the firewall past the ECU ground connector.

This leads directly to the fuel pump where one can attach a 18g wire to it and touch the positive post to the battery.

This runs the pump and if you squeeze the fuel line going into the rail, you can feel pressure build up when you touch the battery.

Those are all awesome suggestions! Well this is what I accomplished during the weekend... Changed fuel rail + regulator, changed out the temp sensor and rewired the plug nicely (it was spliced like crap from previous owner), fixed wiring on the MAF sensor (from previous owner splicing it to install a 2g MAF and then reverting to a 1g MAF and taping the wires together), replaced fuel filter (the gas that came out of the old one seemed to be very clean despite the appearance of the filter itself), unplugged ECU to check the wiring by the 3 ECU plugs and... my heart dropped

The wiring on the plugs are spliced to hell! I don't know if this has a lot to do with it, but I mean I daily drove this car last year with no issues. when it was cold was when the car would act retarded but aside from that it was fine. Except from when a buddy of mine installed the narrowband and then we put the ECU in it's original place, while driving, the car would buck and die out, so I just left the ECU sitting on the floorboard and the problem went away. However, I had never actually untapped it to see the real damage... There are some soldered wires, some spliced wires, some bent and tied down wires, the list goes on... What do I do?!?!? Could this be the issue?

Thanks again for all the help guys. Yesterday I just felt like putting fire to the damn car and calling it a day. on top of all this, while trying to troubleshoot the car, it's been pissing coolant cause the water pump gasket went out from the car sitting in a garage all winter

At this point I'm thinking about getting a new wiring harness... the splices are super close to the plugs themselves. What sucks about all this is that last week I had JUST ordered a timing belt kit with the water pump, pullies, belts, tensioner, etc. A whole engine gasket kit from the oil pan to the valve cover, a new oil pan I haven't installed, bought a repair manual, viton valve stem seals, and was just about to order the balance shaft elimination kit from STM and a BUNCH of other parts but now I don't know if I should...

 

[DogWhistle]

:...unplugged ECU to check the wiring by the 3 ECU plugs and... my heart dropped...

The wiring on the plugs are spliced to hell!

Thanks again for all the help guys. Yesterday I just felt like putting fire to the damn car and calling it a day. on top of all this, while trying to troubleshoot the car, it's been pissing coolant cause the water pump gasket went out from the car sitting in a garage all winter

At this point I'm thinking about getting a new wiring harness... the splices are super close to the plugs themselves. What sucks about all this is that last week I had JUST ordered a timing belt kit with the water pump, pullies, belts, tensioner, etc. A whole engine gasket kit from the oil pan to the valve cover, a new oil pan I haven't installed, bought a repair manual, viton valve stem seals, and was just about to order the balance shaft elimination kit from STM and a BUNCH of other parts but now I don't know if I should...

Welcome to DSM ownership. It's a love/hate relationship that will test your patience, and mechanical skills for years to come.

When they run, nothin' is more fun!

Keep the parts you've got on order. You'll need them eventually.

 

[Boosted_Jedi]

That's true. I have owned: 87 chrysler conquest tsi/90 GSX/97GST Spyder/93 TSI AWD/91 GSX (parts car)/and finally this 90 GSX... ask me what I did with the other ones, or rather what they did to me </3 The problem is I have little to none mechanical experience, but compared to 7 years ago, when I first got into DSM's i've learned a little... but not enough to get rid of DSM's and never buy one again hahahaha...