I have this strange problem with my Nissan Sentra 2002(80K miles). When it is about 90 deg F outside and driven more than about 10 miles the engine seems to miss badly(like for e.g. when you run out of fuel). The tacho also flips around during this. This gradually becomes more frequent until the engine finally stalls. After about half an hour the car runs fine until the engine heats up again.
In the winter however there have been no problems driving these distances.
Last summer I took it to the dealer when the check engine light came on and they decoded and said I needed to replace all 4 ignition coils and reset the check engine. I bought the coils and took them to the local mechanic but he said that the coils may not be the problem at all and even if it was you don't need to replace all 4 of them. He said he could fix it by decoding the code the next time the check engine light came on. However it hasn't come on yet and this problem is persistent. I had the coils returned.
Research on the internet shows up that the bad ignition coils can cause similar problems.
Any idea what might be the problem here and what is the best possible way to fix it.