QuestionThe car tries to start on intial key turn, and typically on the fourth strats just fine, regarding the letting it run a few minutes means, that it wont "bog" out when slight gas is applied with no engine bucking, if I try to gas it right away I get major hesitiation. Thanks for the air leak (vacum issues) as it is hard to tell I will check all connections, even though they seam fine, can I soap up the connections? to get a visual confirmation?
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Followup To
Question -
I have a 2000 Hyundai Accent with 45,000 miles, it's a 5 speed. My check engine light is on, car has extremely bad acceleration, when I appy moderate to heavy pedal pressure the car "bogs" down and seems to starve for gas, or maybe seems to choke out. When I apply steady pressure the car travels well on highway speeds, but no green light go. Changed to #1 o2 sensor above the converter after about 5 miles car ran better, but after another 5 went back to the same, also have changed the fuel filter. I do have to turn the key also about 4 times till it starts and warm up about 3 minutes. AutoZone gave me a single code of PO1128 but can not find it on line, what about an EGR issue and where is it located.
Answer -
The poor acceleration is likely due to the same cause as the P1128 code. This code means that the computer needs to add more fuel than it thinks should be required to maintain the proper mixture when under load (acceleration). You should primarily be looking for any way unmetered air can enter the engine. Typically, this is caused by a vacuum leak (often a hole in the PCV hose), but could also be caused by air leaking into the air bellows between the air flow sensor and throttle body. If you have no vacuum leaks, the air bellows is secure on the throttle body, and there are no holes in the air bellows allowing air to enter, then your air flow sensor is probably defective. You don't have an EGR system on the vehicle, so you'll have no EGR problems.
Hyundai has a very nice technical service bulletin (TSB) describing how to check the air flow sensor, TSB# 01-36-022. It lists comparative values for engine rpm, throttle position sensor, and air flow sensor. You can see this TSB and other service information at www.hmaservice.com. You'll need to register for a free account, and the site requires Internet Explorer.
As for the starting issue, I don't fully understand what you mean. The answers to the following will help me understand the issue and advise you:
1. Do you mean you must turn the key about four times before the car will start? If not, what does turning the key four times accomplish?
2. Does the engine crank when you turn the key without the engine starting? If so, does it crank at normal speed?
3. Have you checked your starting and charging systems?
4. Do you have any trouble codes other than P1128?
5. Why do you let the car warm up for three minutes?
AnswerYou can try applying some liquid to the connections on the vacuum lines to see if it gets sucked in. Usually, a good visual inspection will suffice. You'll need to check the air bellows visually, because there's very little vacuum there, and any leakage probably won't be noticeable.
Based on the way you describe you starting problems, I suspect you may have a problem with your fuel pump. You should check your fuel pressure and also make sure it doesn't bleed down significantly when the car is off.
