98 GS300 Idling and Starting Issue, list of new parts
04-01-14, 12:16 AM
#46
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04-01-14, 07:05 AM
#47
The same way or throttle map changes from ect to pwr mode....A different curve is need to the extra air flow and intake gets....I'm not sure exactly the process but I would assume it might be an ob2 attachment or possibly a physical ecu mod to process the data the iacv and maf sensor are sending the ecu properly....I'll look more into it though
04-01-14, 08:42 AM
#48
Found it....srt intake comes with its own computer that plugs into your ecu and translates and accommodates for the higher flow to boost power at all rpm ranges and boost fuel economy....so basically it's the buffer for the ecu to adapt to the new equipment....that intake all included is about 500 bucks
04-01-14, 06:30 PM
#49
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I changed the whole throttle body, have same issue,
I moved the TPS all the way to one side and I got a engine light, moved it to the other side and now it idles and drives fine.... later got code for lean bank 1 again...
any ideas before i do ecu....
I moved the TPS all the way to one side and I got a engine light, moved it to the other side and now it idles and drives fine.... later got code for lean bank 1 again...
any ideas before i do ecu....
04-01-14, 07:57 PM
#51
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thank you, is that dealer only since you need to program it? or can i just buy a used ecu....
should I bother replacing the coils and another fuel pressure regulator , only thing left on my list that not denso or toyota...
should I bother replacing the coils and another fuel pressure regulator , only thing left on my list that not denso or toyota...
04-01-14, 08:08 PM
#52
Coil packs could be one of the issues...It's on the list of maintenance items anyway....and ecu I would Def suggest having a professional look at Maybe not the dealership though....I new ecu would be quite pricey...A used one as long as it's tested clean would be the best bet
04-01-14, 11:17 PM
#53
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Found it....srt intake comes with its own computer that plugs into your ecu and translates and accommodates for the higher flow to boost power at all rpm ranges and boost fuel economy....so basically it's the buffer for the ecu to adapt to the new equipment....that intake all included is about 500 bucks
04-02-14, 06:54 AM
#54
The price isn't really that bad considering what you get.....it's meant to be in conjunction with a high flow srt intake manifold so it's a stepping stone really because the new manifold requires the ecu mod anyway....but urs throwing lean codes is probably because you have a loose clamp or vac hose somewhere....The codes doesn't necessarily mean ur getting more air from the intake side of the maf sensor it could be somewhere else too....especially on ur V8 that's a really short and basic setup no matter what....could just be something small
04-02-14, 07:13 AM
#55
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The price isn't really that bad considering what you get.....it's meant to be in conjunction with a high flow srt intake manifold so it's a stepping stone really because the new manifold requires the ecu mod anyway....but urs throwing lean codes is probably because you have a loose clamp or vac hose somewhere....The codes doesn't necessarily mean ur getting more air from the intake side of the maf sensor it could be somewhere else too....especially on ur V8 that's a really short and basic setup no matter what....could just be something small
04-02-14, 07:31 AM
#56
Yes bad Coil packs will cause haywire that makes sense....same thing I've suggested to OP....but he's already replaced everything else already so he might as well....One thing you did I think he should do though is a visit to the dealership at least once....
04-02-14, 08:35 AM
#57
Actually, I had this exact same issue with a customers car. Maybe your problem is something else hopefully. However, the customers car really threw me off. It ended up being the rings not having a good seal. Only way to fix his was to pull the engine apart and rebuild it with new rings.
The reason it threw me off is because every time he brought it to me, the car would start, run, and drive perfectly. I could never replicate the issue until I got him to drop the car off with me. I couldn't replicate the issue because there was no problem if the engine was warmed up. The problem only showed when the car was cold after sitting a day. The car would run rough or take a few seconds to fire up. I did some diagnostics and did a compression test and it read pretty low. The car did not have any symptoms of low compression. It ran great when warmed up , ad no misfires, and it didn't burn any oil at all. However, it ended up having low compression in the rings. It's also extremely rare for these engines to have ring issues. This was my first case of seeing it actually. Once the engine warms up, the pistons and rings expand, the clearances tighten up and the compression is solid. This explains why its rough on cold startup and then perfect when warmed up.
Hopefully yours won't have the same problem, but do a compression test to rule out the rings. I have had this car in and out a few times. I changed the fuel pump, filter, injectors, and spark plugs. I never though to check the compression which was my mistake, but the car also did not have any symptoms of low compression when the car was warmed up either.
The reason it threw me off is because every time he brought it to me, the car would start, run, and drive perfectly. I could never replicate the issue until I got him to drop the car off with me. I couldn't replicate the issue because there was no problem if the engine was warmed up. The problem only showed when the car was cold after sitting a day. The car would run rough or take a few seconds to fire up. I did some diagnostics and did a compression test and it read pretty low. The car did not have any symptoms of low compression. It ran great when warmed up , ad no misfires, and it didn't burn any oil at all. However, it ended up having low compression in the rings. It's also extremely rare for these engines to have ring issues. This was my first case of seeing it actually. Once the engine warms up, the pistons and rings expand, the clearances tighten up and the compression is solid. This explains why its rough on cold startup and then perfect when warmed up.
Hopefully yours won't have the same problem, but do a compression test to rule out the rings. I have had this car in and out a few times. I changed the fuel pump, filter, injectors, and spark plugs. I never though to check the compression which was my mistake, but the car also did not have any symptoms of low compression when the car was warmed up either.
04-03-14, 12:11 AM
#59
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Should I check the ones on bank 1 only ?
04-03-14, 06:39 AM
#60
Bust out the ohm meter and check the continuity.....same way you check a distibutor that's basically what they take the place of...not sure of the specs for em but all of your symptoms could be coil pack related