Idling Problems Revisited-Injectors?
02-02-2005, 06:44 AM
#1
Idling Problems Revisited-Injectors?
Well, about 4 months ago, I was posting about how my car basically idled like crap after the 370 injectors were installed. It drove fine and dynoed fine, so I didn't think anything of the injectors. But I remember someone saying he had similar issues and it was a leaking injector so I'm leaning toward that as the culprit.
The lack of updates in the last 4 months has been because the car drove for the first time today since the alternator died and I just didn't have time to put the new one in. Anyways, here are the symptoms, maybe someone will be able to point me in the right direction.
The car takes a long time to start, I have to crank it for ~20 seconds to get it to fire up. And when it does, it idles really badly until the car warms up. And it's obvious the car is running crazy rich. Idle EGT's are ~400F and if I sit in the garage while it's idling, I have to change clothes because I'll smell like gas afterwards.
I thought this was related to high fuel pressure since I have a Walbro and it was ~40psi at idle. So I got a SARD and dropped it. This leads to problem #2. Dropping it to 30 psi didn't make it run any better. EGT's are the same, and same richness and hard starting. So I took it down to 26psi and the car actually runs worse. At 26 psi, the car backfires and stalls. If I try to drive it with base FP at 26psi, the car actually won't move. It will hit 1k rpm and start backfiring. Take it back up to 28 psi, problem goes away.
Last night after getting the car running, FP was at 26 psi, and the car actually started blowing fireballs out of the exhaust. Every time it would backfire a 1 ft. long flame would shoot out. Keep in mind, this is at idle, not full throttle.
So I've already changed the plugs, checked the coil packs, checked the charging system and all those are fine. The only thing that I haven't changed out is the injectors so I'm thinking that's the only possible cause now. Problem started when I put them in, but I attributed it to other things. I'm guessing I have a leaky injector or injectors. Otherwise, I can't explain why adjusting the fuel pressure would have no effect on the idling or richness. It should have leaned it out, but it didn't.
I just want to get some other opinions on my theory before I go and drop more money on injectors. Thanks.
The lack of updates in the last 4 months has been because the car drove for the first time today since the alternator died and I just didn't have time to put the new one in. Anyways, here are the symptoms, maybe someone will be able to point me in the right direction.
The car takes a long time to start, I have to crank it for ~20 seconds to get it to fire up. And when it does, it idles really badly until the car warms up. And it's obvious the car is running crazy rich. Idle EGT's are ~400F and if I sit in the garage while it's idling, I have to change clothes because I'll smell like gas afterwards.
I thought this was related to high fuel pressure since I have a Walbro and it was ~40psi at idle. So I got a SARD and dropped it. This leads to problem #2. Dropping it to 30 psi didn't make it run any better. EGT's are the same, and same richness and hard starting. So I took it down to 26psi and the car actually runs worse. At 26 psi, the car backfires and stalls. If I try to drive it with base FP at 26psi, the car actually won't move. It will hit 1k rpm and start backfiring. Take it back up to 28 psi, problem goes away.
Last night after getting the car running, FP was at 26 psi, and the car actually started blowing fireballs out of the exhaust. Every time it would backfire a 1 ft. long flame would shoot out. Keep in mind, this is at idle, not full throttle.
So I've already changed the plugs, checked the coil packs, checked the charging system and all those are fine. The only thing that I haven't changed out is the injectors so I'm thinking that's the only possible cause now. Problem started when I put them in, but I attributed it to other things. I'm guessing I have a leaky injector or injectors. Otherwise, I can't explain why adjusting the fuel pressure would have no effect on the idling or richness. It should have leaned it out, but it didn't.
I just want to get some other opinions on my theory before I go and drop more money on injectors. Thanks.
02-02-2005, 07:51 AM
#2
Guest
Posts: n/a
What are you using for fuel/engine management?
If you let it warm up, turn it off and then start it back up after a minute is it easier or harder to start?
If you think you have a leaky injector, check your fuel pressure after you turn off the car. It should hold pretty steady and slowly back down. If it drops to zero in a matter of seconds, most likely you have a leaky injector. Did all the spark plugs look the same when you changed them? black?
Any ECU codes? how are your O2 sensors
If you let it warm up, turn it off and then start it back up after a minute is it easier or harder to start?
If you think you have a leaky injector, check your fuel pressure after you turn off the car. It should hold pretty steady and slowly back down. If it drops to zero in a matter of seconds, most likely you have a leaky injector. Did all the spark plugs look the same when you changed them? black?
Any ECU codes? how are your O2 sensors
02-02-2005, 08:01 AM
#3
e-manage with the injector harness, SARD to lower base fuel pressure.
If I warm it up, shut it down and then start it back up in under 1 min., it starts easier. If I let it sit for a few minutes, it's about the same as cold startup.
Fuel pressure holds steady when I shut the car down. The plugs all looked similar when I pulled them. Black, and they all smelled heavily of gas.
Only ECU codes are for the O2 sensors since I have no cat.
If I warm it up, shut it down and then start it back up in under 1 min., it starts easier. If I let it sit for a few minutes, it's about the same as cold startup.
Fuel pressure holds steady when I shut the car down. The plugs all looked similar when I pulled them. Black, and they all smelled heavily of gas.
Only ECU codes are for the O2 sensors since I have no cat.
Originally Posted by superdave2
What are you using for fuel/engine management?
If you let it warm up, turn it off and then start it back up after a minute is it easier or harder to start?
If you think you have a leaky injector, check your fuel pressure after you turn off the car. It should hold pretty steady and slowly back down. If it drops to zero in a matter of seconds, most likely you have a leaky injector. Did all the spark plugs look the same when you changed them? black?
Any ECU codes? how are your O2 sensors
If you let it warm up, turn it off and then start it back up after a minute is it easier or harder to start?
If you think you have a leaky injector, check your fuel pressure after you turn off the car. It should hold pretty steady and slowly back down. If it drops to zero in a matter of seconds, most likely you have a leaky injector. Did all the spark plugs look the same when you changed them? black?
Any ECU codes? how are your O2 sensors
02-02-2005, 08:21 AM
#6
Guest
Posts: n/a
It doesn't sound like leaky injector(s). Did you do the test pipes at the same time you did the injectors? I would think maybe your lack of O2 sensors is causing the problem, but that doesn't explain the hard start. They could definately be contributing to your poor idle though
Maybe your coolant temp sensor? They are often attributed to cold start problems.
Maybe your coolant temp sensor? They are often attributed to cold start problems.
02-02-2005, 08:27 AM
#7
Moderator who thinks he is better than us with his I30
iTrader: (8)
Join Date: May 2002
Posts: 9,335
Originally Posted by Red Max
As some of you may know I ordered the 590's from SuperDave, Well I finally got a chance to put them in. After the install, I tried to start the car, but to no avail the car wouldn't start!!! Which sucked! so I called my good ole friend Mardigras who told me that it was because the cold start feature in the ecu was dumping too much fuel in the car. So I wired up a push button start and the car Idles fine. I have not had a chance to drive the car yet because it's snowing right now but. I have revd it out to 5 grand and so far so good.
02-02-2005, 08:29 AM
#8
Injectors were done first, and that's when the problem immediately started. Test pipe was done a few months later.
O2 sensors are in the car, but they're just throwing codes because of the lack of a cat.
At idle, the A/F is ~14.5/1.
It just seems that my motor is flooding. Also forgot to mention, even when the car warms up, it it idles lumpy, like it's got a big cam in it.
O2 sensors are in the car, but they're just throwing codes because of the lack of a cat.
At idle, the A/F is ~14.5/1.
It just seems that my motor is flooding. Also forgot to mention, even when the car warms up, it it idles lumpy, like it's got a big cam in it.
Originally Posted by superdave2
It doesn't sound like leaky injector(s). Did you do the test pipes at the same time you did the injectors? I would think maybe your lack of O2 sensors is causing the problem, but that doesn't explain the hard start. They could definately be contributing to your poor idle though
Maybe your coolant temp sensor? They are often attributed to cold start problems.
Maybe your coolant temp sensor? They are often attributed to cold start problems.
02-02-2005, 09:14 AM
#10
Senior Member
Join Date: Mar 2001
Posts: 413
The car was backfiring and belching fireballs till the neighbors got pissed last night. Nothing like trying to disconnect jumper cables and having to time your moves to avoid the flames out of the tailpipe and getting covered in raw gas.
The last time it dyno'd before the alternator went out it was down about 20whp which was probably due to fouled plugs. We are in desperate need of new injectors and more fuel tuning. 3" w/ test pipe definitely isn't the most subtle way of making power.
We need a better solution than the BEGI/Emanage/SARD/370cc combo we're running now. They're pretty much maxed out as is and the inability to idle isn't helping either.
I'll see if I can post up the emanage settings later tonight but they'll probably be different once it goes back on the dyno w/ the wideband for 10psi.
The new alternator is showing 14.3 volts at idle but the car died again on the way to the shop. It killed an Optima in the process so this battery drain thing is getting annoying.
The last time it dyno'd before the alternator went out it was down about 20whp which was probably due to fouled plugs. We are in desperate need of new injectors and more fuel tuning. 3" w/ test pipe definitely isn't the most subtle way of making power.
We need a better solution than the BEGI/Emanage/SARD/370cc combo we're running now. They're pretty much maxed out as is and the inability to idle isn't helping either.
I'll see if I can post up the emanage settings later tonight but they'll probably be different once it goes back on the dyno w/ the wideband for 10psi.
The new alternator is showing 14.3 volts at idle but the car died again on the way to the shop. It killed an Optima in the process so this battery drain thing is getting annoying.
02-02-2005, 09:23 AM
#11
The idle A/F ratio is fine, and I think idle A/F ratios are usually 14-16 to 1 (depending on the vehicle...so how can it be running as rich as you say at idle with a 14.5 to 1 ratio? That's kinda confusing to me...
Sounds like there is a leak somewhere, but the A/F reading has to be off if that is the case. Did you check the seals around the injectors? I'm at a loss with what info you have offered...
Sounds like there is a leak somewhere, but the A/F reading has to be off if that is the case. Did you check the seals around the injectors? I'm at a loss with what info you have offered...
02-02-2005, 11:09 AM
#12
This is what is confusing me too, the idle A/F is fine. But the EGT's are so low, and the raw gas smell from the exhaust is overwhelming.
Originally Posted by Quicksilver
The idle A/F ratio is fine, and I think idle A/F ratios are usually 14-16 to 1 (depending on the vehicle...so how can it be running as rich as you say at idle with a 14.5 to 1 ratio? That's kinda confusing to me...
Sounds like there is a leak somewhere, but the A/F reading has to be off if that is the case. Did you check the seals around the injectors? I'm at a loss with what info you have offered...
Sounds like there is a leak somewhere, but the A/F reading has to be off if that is the case. Did you check the seals around the injectors? I'm at a loss with what info you have offered...
02-02-2005, 12:03 PM
#13
Originally Posted by Mishap
The car was backfiring and belching fireballs till the neighbors got pissed last night. Nothing like trying to disconnect jumper cables and having to time your moves to avoid the flames out of the tailpipe and getting covered in raw gas.
The last time it dyno'd before the alternator went out it was down about 20whp which was probably due to fouled plugs. We are in desperate need of new injectors and more fuel tuning. 3" w/ test pipe definitely isn't the most subtle way of making power.
We need a better solution than the BEGI/Emanage/SARD/370cc combo we're running now. They're pretty much maxed out as is and the inability to idle isn't helping either.
I'll see if I can post up the emanage settings later tonight but they'll probably be different once it goes back on the dyno w/ the wideband for 10psi.
The new alternator is showing 14.3 volts at idle but the car died again on the way to the shop. It killed an Optima in the process so this battery drain thing is getting annoying.
The last time it dyno'd before the alternator went out it was down about 20whp which was probably due to fouled plugs. We are in desperate need of new injectors and more fuel tuning. 3" w/ test pipe definitely isn't the most subtle way of making power.
We need a better solution than the BEGI/Emanage/SARD/370cc combo we're running now. They're pretty much maxed out as is and the inability to idle isn't helping either.
I'll see if I can post up the emanage settings later tonight but they'll probably be different once it goes back on the dyno w/ the wideband for 10psi.
The new alternator is showing 14.3 volts at idle but the car died again on the way to the shop. It killed an Optima in the process so this battery drain thing is getting annoying.
The battery dying despite the new alternator means you could have a short somewhere from the battery to the rest of the electrical system...
02-02-2005, 02:30 PM
#14
I couldn't fix your brakes, so I made your horn louder
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Join Date: Jan 2002
Posts: 2,588
I installed my 555cc injectors and I had the exact same symptoms - the bottem o rings - the ones that sit inside the lower plenum - are pretty flimsy and tear really easily. They kept tearing and I ended up pulling the fuel rail off 3 times to get it right finally. I had the same problem - fireballs shooting out the back and running ridiculously rich. I tried to adjust with the e-manage and the fpr and it was clear that fuel was still dumping in because of the injector.
I'd definately start with the lower o rings first and work from there.
Even if the o2 sensors were at fault - they wouldnt be dumping THAT much fuel in.
I'd definately start with the lower o rings first and work from there.
Even if the o2 sensors were at fault - they wouldnt be dumping THAT much fuel in.
02-02-2005, 02:34 PM
#15
Did you have starting problems too? Or is that an unrelated issue? I'm probably going to switch to bigger injectors anyways in the next few weeks, so hopefully if I'm careful during the install, the new injectors will solve this problem.
Originally Posted by seximagtr
I installed my 555cc injectors and I had the exact same symptoms - the bottem o rings - the ones that sit inside the lower plenum - are pretty flimsy and tear really easily. They kept tearing and I ended up pulling the fuel rail off 3 times to get it right finally. I had the same problem - fireballs shooting out the back and running ridiculously rich. I tried to adjust with the e-manage and the fpr and it was clear that fuel was still dumping in because of the injector.
I'd definately start with the lower o rings first and work from there.
Even if the o2 sensors were at fault - they wouldnt be dumping THAT much fuel in.
I'd definately start with the lower o rings first and work from there.
Even if the o2 sensors were at fault - they wouldnt be dumping THAT much fuel in.
02-02-2005, 06:07 PM
#16
I couldn't fix your brakes, so I made your horn louder
iTrader: (6)
Join Date: Jan 2002
Posts: 2,588
definately had starting problems - the only way i could get it to start was to hold the pedal all the way down to tell the ecu not to add any more fuel - and after 10 sec or more of cranking it'd start.
02-02-2005, 08:34 PM
#18
this sounds a lot like the o-ring problem i was having when i first put the 370s in. like sexima said the o-rings are very sensative when you are installing them and tend to crack/rip/tear. if one tears then lots of fuel is being allowed into the motor at idle.
i was getting a huge white cloud of gas out of the tailpipe.
you have to make sure you lube the o-rings before putting them in so they slide into place with less friction. once i replaced the torn o-ring and lubed it...the car idled and ran perfectly.
i hope its as simple a problem as that for you. good luck.
i was getting a huge white cloud of gas out of the tailpipe.
you have to make sure you lube the o-rings before putting them in so they slide into place with less friction. once i replaced the torn o-ring and lubed it...the car idled and ran perfectly.
i hope its as simple a problem as that for you. good luck.
02-02-2005, 10:35 PM
#20
Originally Posted by seximagtr
I installed my 555cc injectors and I had the exact same symptoms - the bottem o rings - the ones that sit inside the lower plenum - are pretty flimsy and tear really easily. They kept tearing and I ended up pulling the fuel rail off 3 times to get it right finally. I had the same problem - fireballs shooting out the back and running ridiculously rich. I tried to adjust with the e-manage and the fpr and it was clear that fuel was still dumping in because of the injector.
I'd definately start with the lower o rings first and work from there.
Even if the o2 sensors were at fault - they wouldnt be dumping THAT much fuel in.
I'd definately start with the lower o rings first and work from there.
Even if the o2 sensors were at fault - they wouldnt be dumping THAT much fuel in.
02-03-2005, 07:32 AM
#21
I varies, it does it in summer on warm days also. The idle is just a little better if it's warm out.
sexima, you're describing my exact problems. I'll pull the injectors immediately.
Corey, I don't have the Z MAF yet, that is going in today and we are switching the base injector size to 370.
sexima, you're describing my exact problems. I'll pull the injectors immediately.
Corey, I don't have the Z MAF yet, that is going in today and we are switching the base injector size to 370.
Originally Posted by Nealoc187
What is the outside temp when you are having these hard start problems?
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